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5 Best Watermakers for Sailboats

5 Best Watermakers for Sailboats | Life of Sailing

Last Updated by

Daniel Wade

June 15, 2022

With the right Watermaker, the ocean becomes an almost immeasurable supply of fresh and clean drinking water to keep you hydrated during your offshore sailing adventures.

Many sailors do spend a lot of their time and money on various parts of the sailboat including the sails, engine, electronics, and generators especially when preparing for long-distance voyages.

While there's absolutely nothing wrong with this, they often overlook one crucial part of general human survival: having an ample supply of fresh drinking water.

Whether you have freshwater drinking tanks on your sailboat or planning to cruise in areas where you can easily access clean drinking water, the hassle involved in having to come to the dock to fill the water tanks can be quite overwhelming.

This is exactly why you need to find the best watermakers for sailboats.

Like many other nautical technologies, watermakers have significantly advanced in the last few decades to become very efficient and more reliable. They're no longer a luxury on your sailboat but a necessity. Better still, watermakers have become relatively affordable and are meant to keep you hydrated as you explore areas that do not have clean and fresh drinking water.

In this article, we'll take a look at how watermaker systems work, highlight its benefits, and highlight the best sailboat watermakers on the market right now. At the end of this read, you should be able to choose the best watermaker for your sailboat.

Table of contents

Benefits of Having a Watermaker on Your Sailboat

The freedom and security that come with having full water tanks on your sailboat are of immense importance, especially if you're cruising in an area where fresh drinking water is hard to come by and quite expensive when you do. As such, having a watermaker aboard your sailboat is no longer a luxury like it used to be in the past. With a steady supply of fresh and clean water, your life on the sailboat will be a lot better. This is because you'll have enough clean water to drink, cook, wash, and shower, which is beneficial if you want to enjoy your sailing adventures.

Honestly speaking, many sailors do not actually need a watermaker. Well, if you're planning to sail just near the shores, then there's a chance that you can easily access fresh and clean water by the dock. But this can be limiting if you've been dreaming of going off the grid and sailing to some exotic and unknown places in the world.

With that in mind, a watermaker makes a lot of sense to most sailors. You won't have to worry about having to carry aboard gallons of fresh water for cooking and drinking during your voyage. You won't have to treat freshwater as a precious commodity that must last until you can refill at the next port. With a watermaker, you can simply go ocean crossing without worrying about running out of water.

A watermaker allows you to have a steady supply of fresh and clean water to keep everybody well-hydrated and healthy. You can clean the water anytime you feel like and all you have to do is replace the filter once in a while and you'll be good to go. In essence, a watermaker is probably one of the most important equipment to have aboard your sailboat, so installing it is of great importance if you're a serious sailor.

The Basics of Modern Marine Watermakers

Modern marine watermakers essentially follow the principle of reverse-osmosis to produce pure, drinking water from seawater. During this process and through very high pressure, seawater is forced through a semipermeable membrane that only allows freshwater molecules to pass through it but not salt, bacteria, or any other organic material. The newly made pure, drinking water is then piped to the sailboat's water tanks while the leftover (brine) is discharged overboard.

Even though marine watermakers may differ in the type of pump that's employed and how it is driven, this is one of the most important features in every watermaker. In most cases, water can be electrically pumped or powered directly off the boat's engine. If you have an AC generator or alternator on your boat, it would make much sense to use the AC output to drive the watermaker directly. You can also choose the DC-powered models if you rely on renewable energy from solar or wind. Alternatively, you can still go for AC-powered watermakers but you'll have to buy an inverter.

All in all, DC-powered watermakers are more efficient since they integrate a power-saving energy recovery system (ERS). You must, however, keep in mind that your energy consumption levels might be quite high if you're sailing in colder and saltier areas. This is because the water purification process might be a bit slower in such areas. As such, you should consider investing in a more high-powered watermaker system if you will be sailing in colder and saltier areas than if you're planning to sail more in warm and less salty areas.

As far as an engine-driven watermaker is concerned, you should mount the high-pressure pump on the engine so that it can be belt-driven using an automatic clutch. An engine-driven watermaker should be your first option if you want large quantities of fresh drinking water. This is more productive than AC or DC-powered watermakers. Even with a relatively small engine, this setup has an automatic regulator that constantly pumps the water. With that in mind, engine-driven watermakers are ideal if you want to reduce your energy consumption. To put it into perspective, an engine-driven watermaker can lower energy consumption by an enormous 80%, especially when compared with conventional AC or DC-powered watermaker systems.

How to Choose the Best Watermaker for Your Sailboat

There are many factors to consider when looking for the best watermakers for your sailboat. Here are the most important things to consider.

Your Freshwater Needs

One of the most important things to consider before spending your money on a watermaker is your freshwater needs. What quantity would be enough to keep you going on your sailing adventure? While the quantity might differ from one sailor to the other or from one boat to the other, you should consider the number of gallons that a particular watermaker can produce per day. This will help you in choosing the ideal watermaker; a model that will ensure that you never run out of water. Do not underestimate your water needs, especially if you're planning to sail with your children or if you're planning to stay on the boat for an extended period of time.

Do you have enough space on your vessel to accommodate the type of watermaker you're looking to buy? While most watermakers are designed to fit in the smallest of space, you should consider the actual size of the watermaker and find out whether you have enough space on your vessel to fix it.

Watermakers can run on electricity, renewable energy such as wind and solar (if you have them on your vessel), or both. When looking for the perfect watermaker, you should consider how to power it and whether or not the watermaker has low-energy consumption, which is definitely a great feature. Again, there are also engine-driven watermakers, so it's important to know exactly what you're going for.

Maintenance

Watermakers have a reputation for being difficult to maintain. Fortunately, the equipment and components have improved in the last few years so you should go for a model that's easy to maintain. You should use the watermaker in water bodies that look good, You should avoid using the watermaker in dirty harbors as you may have to change the filters every so often or even damage your watermaker altogether.

Best Watermakers for Sailboats

Let's take a look at the best watermakers available on the market right now.

The Ultra Whisper

Engineered by limited electrical options that can run on either DC or AC, THE Ultra Whisper by Sea Recovery is one of the best watermakers currently available on the market. In addition to being very quiet, this watermaker features an automatic operation that requires very minimal operator adjustment.

This watermaker is ideal for small powerboats and sailboats since it can serve as an efficient water supply. This model boasts about a 75% reduction in power consumption, especially when compared to other models.

  • ‍ Smooth and quiet water production
  • Can produce up to 2,280 liters per day
  • Ideal for small boats
  • It is energy efficient
  • ‍ It might not be perfect for large boats

Echotec Watermaker

If you want a watermaker model that can produce 60 liters per hour flawlessly and with no maintenance apart from changing the filters, look no further than the Echotec Watermaker. This model is designed for ultra-reliable performance and easy customer installation.

This watermaker is made from high-quality components that can withstand the continuous harsh marine environment, making it one of the most durable watermakers on the market. This is essentially a series of modular watermakers ranging from 12-volt to 24-volt DC-powered models. They bring forth energy efficiency, a computerized energy recovery system, and ultimate reliability to ensure that you never run out of fresh drinking water while out there on the sea.

  • ‍ Energy efficient
  • Cost-effective
  • ‍ Comes with a very low speed
  • Not ideal for large boats

Spectra Katadyn PowerSurvivor

As a compact and energy-efficient watermaker, the Spectra Katadyn PowerSurvivor is arguably the most affordable watermaker currently available on the market. We are talking about a model that only requires 4 amps to desalinate water for your sailboat. It can produce 1.5 gallons of fresh drinking water per hour, which is an excellent return for a watermaker of its size.

It is also one of the most portable watermakers around. You can choose to either install it permanently or temporarily in case you want to take it somewhere else. This portability is also essential if you're looking for a space-saving model that can fit in the smallest of compartments. Its simple but rugged design is essential in ensuring that it can perform at its best even in harsh marine conditions. In terms of its power capabilities, this is the only model on the market that will convert to a hand-operated system or manual power if there's a power shortage.

  • ‍ Portable and lightweight
  • Rugged design to withstand harsh marine environments
  • Efficient and reliable
  • Can revert to manual power if there's a power shortage
  • Perfect for off-grid sailing
  • ‍ Gasoline or diesel can easily damage the semi-permeable membrane

Village Marine - Little Wonder Series

Whether you're looking for a watermaker for your small sailboat or looking for a watermaker that can efficiently serve those huge yachts, the Village Marine Little Wonder Series provides everything. This model is meant for experienced sailors who are looking for various capacity options. This watermaker weighs just about 69 pounds but can produce nearly 180 gallons of fresh drinking water each day.

Designed with a low RPM high-pressure pump, this model remains one of the most efficient and economical watermakers on the market. That's not all; this watermaker is designed with corrosion-resistant features and is one of the most serviceable watermakers in the game. It is reliable, quiet, and portable; all factors that make a watermaker great.

  • ‍ Easy to operate
  • Corrosion-resistant
  • Easy to maintain
  • Quiet and versatile
  • ‍ It doesn't have automatic adjustment controls

Ventura 150 Watermaker

This is one of the most versatile watermakers on the market. It can use both electricity and renewable energy. This model is engineered to be lightweight and energy-efficient and its compact and modular design makes it a great option if you're looking for a watermaker that's easy to use and install in confined spaces.

The Ventura 150 watermaker is highly efficient as it can produce over 6 gallons of water an hour, which makes it quite perfect for small vessels. This sailboat watermaker features a controller that allows you to operate and monitor the device remotely. It also has the auto store button that will automatically flash the system after every five days.

This watermaker is quiet and surprisingly compact despite its ability to produce about 150 gallons of water per day. It also gives you the option of going for the automated manual or manual model.

  • ‍ Very versatile
  • Can use both electricity and renewable energy power
  • It is smooth and quiet
  • It is compact and lightweight
  • ‍ The manual model has analog controls

To this end, it's easy to see that having an ideal watermaker aboard your vessel is one of the first crucial steps towards being self-sufficient and sustainable. With a watermaker, you'll be able to access fresh drinking water at all times when sailing even in far-flung places. Most of these models are well-constructed and incorporate some of the best technologies that make them efficient, reliable, and easy to install, use, and maintain.

So when it comes to choosing the best watermaker for your sailboat, it may all come down to what is ideal for you in terms of energy consumption, efficiency, the quantity of water produced, among many other things. With an ideal watermaker, you can remain off the grid for as long as you want without ever worrying about running out of water and this is of great importance in enjoying your sailing adventures.

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I've personally had thousands of questions about sailing and sailboats over the years. As I learn and experience sailing, and the community, I share the answers that work and make sense to me, here on Life of Sailing.

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Keeping Water Clean and Fresh

Good old bleach is great, but treatment tabs have advantages..

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Beyond protecting the tank with basic filtration and securing the tank vent, you also need to take further action to ensure water quality, as the tank and its contents will always be far from sterile.

Municipal water is filtered to remove turbidity, disinfected (typically with chlorine, ozone or ultraviolet light), filtered once more (often very fine filtration to remove cryptosporidium cysts, which resist disinfection), and disinfected once more (with chlorine or chloramine) to protect the water while its in the distribution system. However, since we are storing the water on our boats, this process of secondary disinfection becomes our responsibility. So what are the options for treating water that is already in an onboard tank?

In the U.S., the chlorine residual from municipal waters secondary disinfection is usually enough to keep tank water clean. In most cases, a sufficient amount of chlorine—1 part per million (ppm)—from the municipal treatment process carries into the boats tank. You can easily check the amount of chlorine in your tank by using the test strips designed for aquariums. We like the Tetra EasyStrips (about 69 cents per test), which simultaneously test for nitrate, nitrite, hardness, chlorine, alkalinity, and pH.

Star brite Water Treatment

Over-chlorinating, whether with bleach or commercial freshening chemicals, can shorten the life of elastomers in your plumbing. Chlorine is a leading cause of death for freshwater pump impellers. Excess chlorine also shortens the life of tap-water polishing filters. Finally, excess chlorine has negative health effects and is limited to 4 ppm by U.S. drinking water standards (0.5-1 ppm is normal). If you find that your tank lacks any residual chlorine, there are a few treatment options:

Bleach: Household bleach (unscented) typically contains 5.25 percent sodium hypochlorite, which breaks down in water into hypochlorous acid and several other useful sterilizing agents. Only a few parts per million are needed to effectively deactivate bacteria and viruses, typically within two to 30 minutes, depending on temperature and contaminant levels. However, there are a few caveats. The water must be reasonably free of physical dirt, since the bleach will expend itself oxidizing organic materials, and bacteria will hide within the dirt.

How much bleach should you use? More is not always better. The standard recommendation for emergency disinfection is 1 tablespoon per 10 gallons; this standard is frequently repeated in boating and camping texts. This allows for organic compounds chlorine demand and provides enough kick-20 ppm of free chlorine-to reach micro-organisms buried inside small dirt particles. This is appropriate for sanitizing and for dirty water, but it is overkill for routine treatment of good quality water, at least 10 times more than is typically used in tap water.

For treating water that is clear and chlorinated at the tap, 1 teaspoon of bleach per 50 gallons will provide a 2 ppm booster, the very most that should be needed. Chlorine aftertaste is the most common onboard water-quality complaint; however, chlorine at the tank can be efficiently removed with carbon filtration. In fact, chlorination is vital to performance of downstream filtration, controlling growth within the filter.

Dichlorisocyanurinate: Common in swimming pool tablets, chlorine in this form has several advantages. Chlorine levels are stabilized by a chemical equilibrium, resulting in a more stable and more durable treatment, and reducing the amount required. Additionally, the released chlorine generates cyanuric acid, an effective corrosion inhibitor for aluminum, reducing aluminum corrosion by 10 to 40 times compared to bleach treatment. Both the U.S. Environmental Protection Agency (EPA) and World Health Organization (WHO) approve this method.

Hydrogen peroxide: Internet forums frequently suggest the use of hydrogen peroxide (H2O2) as a bleach alternative, but because of the lack of regulatory guidance (neither the EPA nor WHO recommend it as a treatment solely on its own) and numerous well-known shortcomings, we cannot recommend it as a sterilizing agent.

Quaternary amines: Common in non-bleach, anti-bacterial surface cleaners and hand soaps, quaternary amines (e.g. benzalkonium chloride) are effective against bacteria, algae, and most viruses. However, they are typically very toxic to marine invertebrates (a few ppb is lethal), so use around the water should be limited. If you are sterilizing a tank with these, they should be flushed from the system before drinking.

Ultraviolet light (UV): Ultraviolet light, specifically those wavelengths between 250 and 300 nanometers, is a very effective sterilizing agent. UV is typically employed as a final sterilizing step, in the plumbing, and not in the tank. Weve tested two portable UV devices for personal water purification, the Steripen (see PS, April 2008 online) and the CamelBak All Clear (see Chandlery , PS, June 2013 online).

Desert island tip: Lets say youre down to your last bottle of water, and although you have fresh water available, you have no chemicals or filters to make it safe to drink. What to do? WHO has studied this problem, as it is not unusual in the wake of a hurricane or flood.

First, collect the best water you can find in clear water bottles, allow the water to settle, and filter it through cloth until it is reasonably clear. Fill the bottles about three-quarters full, shaking vigorously to oxygenate the water, and then, leave the water in full sun (placing the bottles on a reflective surface helps) for three to eight hours. The suns UV will deactivate over 99.9 percent of the pathogens in the bottle.

None of the above methods will remove microscopic parasites (giardia and cryptosporidium). These are shell-like organisms that resist chlorine treatment; water suspected of containing parasitic cysts must be filtered to 0.5 microns to provide physical removal. We will deal with physical filtering at the tap in the final segment of this series.

What We Tested

There are commercial products designed to accomplish the same water-purifying tasks as bleach, but they claim they do it better. For this report, we tested tank-cleaning products, sanitizing chemicals, and tank-freshening chemicals, as well as a dishwasher detergent.

Intended to cleanse funky tanks before sanitizing, tank-cleaning products contain non-bleach cleaners and sanitizing agents. While they should not be needed in a well-maintained system, they may be helpful if things have been let go.

Sanitizing chemicals are for used after cleaning; all are based on chlorine, but the chemistry varies. Tank-freshening chemicals provide disinfection for clean tanks, supplementing the chlorine in the tap water. These are handy when you don’t trust the tap water-perhaps the water has been sitting for a while and seems less than fresh.

How We Tested

We dosed each freshening product into reverse osmosis (RO) water as directed by the manufacturer, measuring free chlorine and observing odor. We then transferred the water into 1-gallon, disposable ice-tea jugs made of thick-walled polyethylene, which we felt presented a reasonable surrogate for a lightly contaminated polyethylene water tank. Although well-rinsed when emptied, they had a uniform level of taste and smell saturated into the plastic; we graded how well the chlorine residual endured after 24 hours, and how well residual odor and taste were removed.

We then repeated similar tests for tank cleaning-chemicals and tank-sanitizing chemicals. We also placed aluminum corrosion coupons (SAE 329) in the solutions and graded them after regular checks during a three-week period; chlorine-induced corrosion is a major concern for those with aluminum tanks. Note that all testing was with high-quality RO water; other water types may exhibit some chlorine demand (some bleach is neutralized by the water), and some will contain chlorine. The only way to be certain of dosage is to test with swimming pool strips or equivalent.

We tested tank-cleaning products by soaking contaminated beverage containers and soaking dishes uniformly soiled with dried-on salsa. Water and a bleach solution recommended for sanitizing by the American National Standards Institute (ANSI) were controls.

We also used each of the freshening chemicals during a summer of cruising, dosed as recommended. Because the filling water was variable, we did not attempt any quantitative measurement in the actual onboard field trials. We simply evaluated taste.

Observations

Here is a rundown of some important observations that testers made during the evaluation.

Any additives should be used during the first one-third of the filling process. This allows a thorough mixing. All of the tablets dissolved before the tank was full. For aluminum tanks, dissolve the tablets in a bottle of water first.

Bleach is a handling problem. We settled on a sturdy pint sports drink bottle with a cap that held the required amount. We kept the bottle in a deck locker to avoid dribbling the bleach on clothing, upholstery, or carpet. For annual sanitizing we filled a water bottle with the required dose at home and took only that to the marina. Camco TastePure Freshener contains diluted bleach and is less of a bleaching hazard if spilled. All other products were non-bleaching; nevertheless we would still clean up all spills and keep them away from fabric.

While some of the products left a detectable chlorine smell in the tank, none were noticeable at the tap, even without carbon filtration.

We were concerned about pitting in aluminum tanks. The highest concentrations were in the tank cleaning and sanitation products. Since these are only used once a year for no more than 90 minutes while the tank is being cleaned and flushed, we limited the test coupon exposure to only 48 hours. None of the products caused significant pitting, but Puriclean (dichlorisocyanurinate) was clearly less corrosive to aluminum than other sanitizing treatments. When we tested freshening treatments and tap water, we found the same trend; AquaMega Tabs (also based on dichlorisocyanurinate) were far less damaging than other treatments, and less damaging than tap water alone.

While most disinfecting products are based around 2 to 3 ppm of free chlorine, 0.5 ppm residual chlorine is enough for safe water, and owners of aluminum tanks should buy test tapes and use only the minimum amount of disinfectant required.

We tested some non-chlorine treatments (ozone and hydrogen peroxide), but found these to be either corrosive to aluminum or ineffective. Carefully regulated chlorination is the most sensible treatment.

Tank cleaning chemicals function a little differently than bleach and detergent, dissolving more material without agitation, but not loosening heavier deposits as well as detergent with light agitation. They did perform better than plain water or the ANSI bleach sanitizing solution. All were non-corrosive to aluminum. The sanitizing effect of the quaternary amines and peroxides may be valuable, if the user does not intend to follow cleaning with a bleach sanitizing process.

aluminum coupons

Tank Cleaning Chemicals

Star brite tank cleaner.

Star brites Water Tank and System Flush, also labeled as Aqua Clean Water Tank Flush, is based on alcohol and alkylbenzly chloride, a quaternary amine commonly used in anti-bacterial handsoaps and surface cleaners. It is more potent than plain bleach sanitizing solutions. However, we cannot confirm the effectiveness of this chemistry.

We do not advise adding bleach to the product, as an undesirable reaction will occur. Any bleach sanitizing, if desired, must be a separate step.

Bottom line: Recommended with a bleach follow up if fail-safe sanitizing is required.

Camco Spring Fresh

Camcos Spring Fresh contains a food-grade surfactant and is a better cleaner than plain bleach sanitizing. As with the Star brite, we caution against adding bleach to the product as a bad reaction will occur. If you plan to do bleach sanitizing, do it in a separate step.

Bottom line: Recommended if fail-safe sanitizing is required. Follow up with bleach or Camco Dewinterizer.

Finish PowerBall Tabs

Our research into the chemistry behind tank-sterilizing tabs led us to regular dishwashing tablets. Finish Powerball Tabs were the ones we had on hand, so we included them in the test. They required slightly more agitation than the other test products, but they did a superior job when gentle swirling was added. Like all dishwasher detergents, Powerball Tabs contain a sterilizing agent (in this case, percarbonate, which releases hydrogen peroxide) to prevent the dishwasher from getting nasty. We used 1 tablet per 5 gallons of water, which we felt mimicked the solution used in a dishwasher.

Bottom line: This is the Budget Buy choice, if you have the time to take your boat for a rollicking sail to provide some agitation.

Tank Sanitizing Chemicals

These treatments are meant to be done once a season (often after winter storage) or when you suspect a contaminated tank.

Puriclean Clean Tabs

These tabs are based upon sodium dichlorisocyanurinate, and have the same basic chemistry as AquaMega Tabs (below), but are packaged in a tub suitable for tanks up to 60 gallons. To uses, you dissolve the tabs in about gallon of water, then mix it into the tank and allow it to sit for 1 to 2 hours. This concentration (about 20-30 ppm chlorine) sanitizes any pre-cleaned tank. Testers noted much lower aluminum corrosion rates than other sanitizing products; the aluminum is discolored by the formation of a dark passive layer, which stops further corrosion and pitting.

Bottom line: Recommended. The stable residual and low aluminum corrosion rates make Puriclean Clean Tabs the PS Best Choice among tank sanitizing chemicals.

Star brite Water Shock

A concentrated formula, Star brites Water Shock is intended to clear up any odors and tastes that tank cleaning leaves behind, and to sanitize the tank. It is also recommended for routine freshening at a lower dosage.

Bottom line: We don’t believe this outperforms the ANSI bleach sanitizing procedure (below).

Camco Dewinterizer

Camcos Dewinterizer uses a somewhat lower chlorine content than recommended by ANSI. It is intended to clear-up odors and tastes that tank cleaning left behind, and to sanitize the tank.

Bottom line: We don’t believe this outperforms the ANSI bleach sanitizing procedure.

Tank Freshening, Disinfection Chemicals

These treatments are meant to be done on a routine basis, either to restore freshness to stale water or to maintain clean tanks.

Household Bleach

Unscented, 5.25-percent sodium hypochlorite (household bleach) is sold under countless brands. The baseline for comparison, WHO and the EPA has studied this ad nauseam. A solution of 1 teaspoon per 50 gallons gave us a 2 ppm residual; about right for most tap-water applications. Remember that bleach loses effectiveness after long storage and should not be kept more than six months after opening.

Bottom line: This is far and away the most affordable treatment, but you must measure it yourself-and don’t spill.

tank cleaners

AquaMega Clean Tabs

Based on sodium dichlorisocyanurinate, the AquaMega tablets are available in amounts matched to tank sizes. We observed a more stable residual and much lower aluminum corrosion rates. There was a stable residual for weeks, versus only 48 hours with bleach products. Because of this stable residual, we suspect that the AquaMega tabs dose might be stronger than what most tanks will require for simple freshening.

If you are willing to test your water, you can tailor a smaller dose that more closely mimics the ANSI solution. If the 50-gallon size is more than you need, you can break tabs in half and wrap-up the remainder in the foil pouch for up to one month. Its also available in small pills (Aqua Minitabs) for individual treatments.

Bottom line: The convenient packaging, low corrosion rates, and stable residual made this our Best Choice among tank freshening and disinfection chemicals. It was also our favorite to use.

Star brite Freshener

The Star brite Water Freshener was the only solution in the test lacking the distinctive chlorine odor, but it did not change the odor of our chlorinated tap water. The manufacturer did not share the disinfectant chemistry, so we could not confirm its effectiveness.

Bottom line: While the lack of chlorine smell in the concentrate suggested better tasting water, we observed no difference on the boat.

TastePure Freshener

Based on pre-diluted bleach, TastePure Water Freshener performed much like bleach. The resulting water had a barely discernible chlorine smell, and the taste was fresh.

Bottom line: Recommended as an effective freshening product.

Conclusions

The United States has perhaps the highest quality water in world, regardless of what we read in the papers. Do we need to disinfect if the source water is chlorinated and of high quality? Perhaps not for safety alone, if the tank is cleaned and the water is turned over every few weeks, though often potability is improved. If traveling outside the U.S. or if cautious by nature, providing secondary disinfection is easy and safe.

We like bleach, particularly for annual sanitizing. Its cheap, its known to be effective, and any aftertaste is easily removed with carbon filtering. However, the two test products formulated with dichlorisocyanurinate—AquaMega Tabs for freshening and Puriclean Powder for sanitizing—lasted longer than bleach. We also like AquaMega tablets for convenience; they have a long shelf life and are simple in use, with nothing to measure, nothing to spill, and nothing to return to stowage after use. If your boats not in the water and you can’t agitate your tank, the cleaning chemicals seem to help loosen deposits better than bleach sanitizing solutions and dishwasher detergents. However, dishwasher detergent did very well when a little sloshing was provided.

Although we began this project expecting cheap and effective bleach would win out, the convenience of some of the commercial products won us over.

For sailors with aluminum tanks, we recommend AquaMega Tabs and Puriclean because of much lower corrosion rates-even lower than tap water. Additionally, we believe that the manufacturers recommended dose may be quite conservative; half this amount may be sufficient. We recommend that you buy test strips and use the smallest dose that is detectable or produces any chlorine smell in the tank. Aluminum corrosion will be reduced.

Point-of-use filters will remove any last trace of odor, taste, or contaminating chemicals, leaving water as fresh, pure, and safe as bottled water. The steps we explored in this and the water tank filter report are just as critical as that final filtration step. Protection against biological growth begins at the tank fill and the tank.

Keeping Water Clean and Fresh

  • Preventing and Treating the Tainted Tank

RELATED ARTICLES MORE FROM AUTHOR

27 comments.

Excellent article(s), all 3 of them. I learned a lot. Biggest frustration is sourcing the Best Choice Aqua Mega Tabs. They are not available in the US. I can’t imagine why more marine supply stores don’t offer them.

Stephen, I purchased Aqua Mega Tabs from http://www.TheYachtRigger.com out of Florida.

I seem to be having trouble finding the Aqua Mega Tabs in the US and even in England it seems to be hard to come by and with shipping it will be too expensive. Is there any US source with stock of this product? I tried to leave a message on the www site for Aqua Mega and it did not seem to work. thanks Kent

Try Amazon or Hopkins-Carter (Aqua Mega Tabs).

My mother would like to keep her water clean and free from contamination, which is why she’s thinking of installing a system that will help keep it clean. Well, I also agree with you that it would be smarter to use chlorine too. Thank you for clarifying here as well the importance of sterilizing.

My marina on West River, in Maryland, uses well water. Assuming the well water passes the county or state requirements for potability, how, if at all, does this fact change your recommendation about the amount of bleach to use, i.e., 1 tsp per 50 gal water, where water is clear and chlorinated at tap?

I’m not far from the West River, just 10 miles down the Chesapeake Bay, in Deale, MD. My marina is also on well water, and I’m guessing the well water is similar. Often it goes a little skunky over time, as the sulfate in the well water is converted to sulfide by native bacteria.

The above advice on chlorination assumes potable quality water that is not chlorinated, and is based on EPA, WHO, and ANSI guidance, and on personal experience and testing. It should apply to your well water. For those that use chlorinated tap water, as long as you rinse the hose out well before use, chlorination of the boat’s tank is not required.

My Beneteau Oceanis (2002) manual section on the fresh water system recommends “When the system has not been used for a long period of time, the tanks and pipes should be cleansed with an acetic acid solution (white vinegar).” But I find no mention of acetic acid here. What are your thoughts about this? Thanks Arthur

Excellent question (cleaning plumbing with vinegar) and excellent topic. Unfortunately the manual gives no information beyond this: “When the system has not been used for a long period of time, the tanks and pipes should be cleansed with an acetic acid solution (white vinegar).” I will be digging into this more deeply.

First, avoid contamination of the lines by “pickling” them with polypropylene glycol winterizing chemical, even in warm climates. So long as the solution is greater than 25% glycol there will be no growth. If you skimp on the agent or there is water in the pipes when you start and you use the typical -40F burst point antifreeze, the bugs will use it as food and grow a nice thick film, which is not dangerous itself, but tastes nasty and makes it impossible for chlorine to work properly through the season. The hot water tank and freshwater tanks should be stored empty and dry.

Bleach is the standard and recognized method for sanitizing relatively clean systems. But if there is a substantial film, there can be advantages to soaking with an acid to eat away the film. Vinegar will work, but the literature and PS testing agree that citric acid (Amazon or the grocery store) is 3-5 times more effective both for removing the film and deactivating chlorine resistant bugs, such as gardia. For every descaling, cleaning, and sanitizing use, citric acid is the more effective, less expensive choice. Vinegar is suggested simply because everyone has it in the shelf.

We’re going to follow-up on this topic, since freshwater systems can get nasty.

Hi Drew I appreciate your quick and informative reply, and look forward to studying your follow-up on cleaning fresh water systems with acid.

Good article. We do something different. We have one tank with a 125gal capacity and we do fresh water cooling of both our refrigeration and freezer from this tank. We run the cooling return line through a canister filter using a charcoal filter. Yes that takes the chlorine out of the water. But we also use tank water through another charcoal filter to flush our water maker, so we don’t have to do the capture RO water and use that for flushing. When in the US we use dock water, but we always run the hose for a good bit to clear bacteria in the hose and I suspect the choline in the municipal water help keeps the tank good since we live aboard and fill about every two weeks.

We did a near circumnavigation of 10 years and 35K miles and when we take water off a third world dock we have a triple filter we use. The first filter is 20 micron, the second inline filter is 5 micron and the last inline filter is a half micro filter with a polarized agent that will remove viruses. We hook the hose up to one end of the filter and the other end of the series goes in the tank. Of course we test water before using it to find out the ppm of the ions. If it is over 750ppm we try to do something different.

While we have a water maker, there are some places where you are at a dock, but you would not dare pull the harbor water into your water maker, so the three stage filter works well. Otherwise it is time for day trip to find clean salt water and run the water maker.

Some watermakers use fresh water from the water tank to flush membranes. Did you find that these products damage watermaker membranes?

You do NOT want hypochorite- or chlorine-containing chemicals in the flush water tank. There is a carbon pre-filter to remove the chlorine, but I’d tend to play it safe. A common recommendation is to scrub the tank as practical, shock chlorinate (not a lot–generally a few tablespoons of bleach) the tank at the start of the season, then rinse vigorously and call it good for the year. You will still get a trace of chlorine with city water (about 1 ppm) but the filter can deal with that.

Some watermakers use fresh water from the water tank to flush membranes. Are these products safe for watermaker membranes?

Plain household bleach is becoming harder to discern. Between many options, scented, low foaming, disinfecting etc even just plain bleach is hard to identify on a store shelf with all the advertising hype.

I noticed that sodium dichloroisocyanurate found in Aqua Mega tabs was recommended, but are difficult to find in the US. I wanted to make you aware of a newly available product, Aquatabs-Marine, which uses the same disinfectant compound and is now widely available in the US at http://www.AquamarineWaterSolutions.com . One tablet treats 4 gallons at about 1.2 ppm, so it can be removed by the active carbon filter on the freshwater flush of most watermakers. This is a drinking water quality tablet that is EPA registered, NSF certified and recognized by the WHO as a routine household drinking water disinfectant. I’d be interested to hear your thoughts.

Thank you for this link. I’ve been adding sodium dichloroisocyanurate tablets to my water tank for years, but until now, only the small tabs sufficient to treat ~2 liters were available in the U.S. In the past I resorted to buying the larger tabs from “gray market” sources on ebay and amazon

Good series but mostly applicable to those without a water maker . While tank purification remained one of our concerns, we tap danced around the issue. We developed a simple plan which was to make all our drinking water directly into a couple of dedicated Jerry jugs. The rest of the water used for cooking and ablution was directed into the vessels tankage. For drinking water only, we kept a couple of one litre plastic jugs in the fridge topped up from the two dedicated Jerry jugs. Never had a water purification issue. Most of the time, our water maker product has was about 200 to 250 ppm. Hugh

This is the most thorough boat water treatise I’ve seen yet. Thanks all. Long shelf life bleach is less effective. Get it as fresh as possible. For clear water I use two drops chlorine per gallon, with a contact time of 48 hours before drinking. For immediate consumption I use eight drops per gallon (of un-chlorinated water), which will make me queasy. To get rid of chlorine taste, I use three cap fulls of hydrogen peroxide per gallon of water, and that will kill the chlorine taste. It also de-activates the chlorine. So, for chlorinated water that tastes bad to me, I add hydrogen peroxide to my glass of water a couple minutes before drinking. Peroxide can be added to the tank with equal results, but the chlorine will be de-activated, thereby defeating its purpose. Hydrogen peroxide by itself is basically useless for sanitizing water.

Personally, I won’t drink anything from a tank until I treat it in my glass or bottle. We typically treat a few gallons at a time and put it in containers in the kitchen for people to drink from. Either that or load up with bottled water (wasteful). No one ever got queasy from this technique, and the peroxide imparts a pleasant sweet taste to the water. Maybe a chemist can explain why this does/doesn’t work. Notwithstanding, I’ve been doing water this way for thirty years and no two-step. Cheap and easy.

Hydrogen peroxide can certainly be used to dechlorinate water (it oxidizes the chlorine to chloride–about 0.4 pounds of H2O2 per pound of chlorine is required); this is a common commercial scale method. However, proper sanitation demands that a chlorine residual is maintained in the tank and throughout the plumbing, if only 1 ppm. Subsequent treatment with carbon is VERY effective at removing the chlorine residual. Carbon removes organic materials by adsorbing them on the surface of microscopic pores. It removes chlorine differently, by sacrificial oxidation of the carbon itself, and as a result it can remove a LOT more chlorine, far more efficiently, than removing odors and tastes without chlorination, by adsorption alone.

We do not recommend dechlorination in the tanks by any chemistry. You want a chlorine residual. Remove the chlorine with carbon. We like carbon block filters, because they also remove cysts, an economical and practical two-for-one.

Thank you Drew. I left out something important that we do with water. Sometimes we rent, sometimes we fly our own boat. Anymore, we carry two Steri-pens when we leave municipal water behind. You mention this product above. Ashore in foreign lands we never allow ice in a glass of water, and we don’t eat salads. Rent boat water tanks are sometimes pretty bad smelling, leaving me to wonder what’s in there. Here’s a link to Steri-pens: https://www.katadyngroup.com/us/en/ado-mp-efg-steripen-adventure-opti-uv-water-purifier~p6693 . They run about $70. Not cheap, but it beats the alternative. This was a great article and bears re-posting from time to time.

I just came across this article (March 2023). Unfortunately, like a few others have commented on since 2021, the items that were specifically recommended for aluminum tanks are not available in the US. The Aqua Mega Tabs are not available via Amazon or Hopkins-Carter, nor is the PuraClean for sanitization. There is a product called AquaTabs with same ingredient, but the pills only treat 4 gal vs. the 50 gal, and the price makes it much less cost-effective.

If PS is going to redistribute these articles year after year, it would be great to have them updated for us US subscribers.

Regarding Cleantabs / Aqua Mega Tabs products that are mentioned in this article, please stay tuned for some exciting news around their availability in the US and Canada. The tests are very relevant to US boaters and the availability issue is being addressed.

We are bringing Clean Tabs to North America – Aqua Mega Tabs, Aqua Midi Tabs, Puriclean etc. We hope to start shipping over the next 3-4 months. If you’d like to be kept informed of availability, please sign up for notifications at cleantabs.com

“In the first part of our three-part series covering onboard water quality, we discussed protecting the tank with basic filtration and securing the tank vent.”

Can you link the referenced first part? I can’t find it.

Thanks, -Bruce

https://www.practical-sailor.com/systems-propulsion/filters-for-water-tank-vents https://www.practical-sailor.com/waypoints-tips/onboard-water-treatment/decontaminating-a-tainted-tank

Thanks so much, @Drew. This is what I was looking for.

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Do You Need a Watermaker for Your Sailboat?

  • By Jen Brett
  • Updated: October 2, 2019

spectra newport watermaker

I remember, in the not too distant past, when having a watermaker aboard a cruising boat seemed to be the ultimate luxury. Plenty of sailors considered them too expensive and complicated. Fortunately times have changed. With improved technology and a range of price points on the market, now even average cruising boats of modest means carry a reverse-osmosis system. And really, is there anything that feels better after a day spent sailing and swimming than a hot shower? The freedom and security that come with full water tanks are also a nice bonus, particularly if you’re cruising in an area where fresh water is difficult to come by and pricey when you do.

Choosing a Watermaker

As with any major system, there are many factors to consider when you choose a watermaker. You’ll need to figure out your freshwater needs, the space you have available for the system and how you’re going to power it . Generally speaking, in a reverse-osmosis desalination system the raw water is run through a series of pre-filters, and then a high-pressure pump moves the water through one or more membrane housings. The wastewater, or brine, is released overboard and the product water goes into your water tanks.

Since all of the watermakers that are currently available for cruising sailboats use this process for desalination, the major differences between the systems are how you power the high-pressure pump and the user interface. Powering options include 120/220-volt AC, 12- or 24-volt DC and engine/belt driven. All have their pros and cons.

“The first question I ask a potential customer is ‘Will your boat have a ship’s generator?’” said Rich Boren of Cruise RO Water. “If they plan to have a generator, then the decision to go with a 120-volt high-output watermaker seems natural. While running the generator for battery charging and other loads two to three times per week, they can keep their water tanks full without having to make generator runs just to make water.”

A 12-volt system, such as the Spectra Catalina 300 Mk II or the Horizon Reverse Osmosis Seafari Quest, makes a lot of sense for smaller cruising boats since they don’t need a generator to run and have fairly miserly power consumption. On a breezy, sunny day, a solar panel and/or a wind generator will likely keep up with the demand. “The only difference between 12-volt DC low-output and 120-volt AC high-output watermakers is how the high-pressure pump brings seawater up to the 800 psi needed to drive fresh water through the reverse-osmosis membrane,” Boren said. “The membrane and support equipment, like pre-filtering and plumbing, are the same.”

seafari mini

These systems typically produce anywhere from about 6 to 16 gallons per hour, and some units can do so for about a 1-amp-per-gallon power draw.

“Many smaller sailboats, under 45 feet or so, often utilize solar panels,” said Berkeley Andrews of Parker Hannifin, which produces Sea Recovery, Horizon Reverse Osmosis and Village Marine watermaker systems. “Their entire electrical backbone consists of 12-volt or 24-volt. So they must have a watermaker that can operate on low voltage. These customers have limited amp hours on their batteries, so all of their equipment must be suited to handling this.”

In choosing a watermaker, Bill Edinger, owner of Spectra Watermakers, said to be realistic about water needs. “When helping customers decide which system is right for them, first we like to determine their approximate water usage with questions like ‘How many people are aboard normally? Are you going to be living on the boat full time? Do you have a washing machine? Any children? Are you going to be cruising full time or leaving the boat for extended periods?”

A common error people make is choosing a watermaker that is too small for their needs. “The most common mistake I see cruisers making in their watermaker purchase decision is underestimating how much water it will take them to cruise comfortably,” Boren says. “I’m not talking about the minimal amount of water it takes for the crew to stay alive, because there is a big difference between staying alive and comfort. Selecting a watermaker that will only meet their minimal drinking-water needs but not keep up with the comfort needs of the crew can lead to crew tensions and feeling like camping rather than cruising.”

Remember that “watermakers are rated in gallons of production in a 24-hour period,” Edinger said. “So a 300-gallon-per-day watermaker system sounds like a lot of water. The important thing is that it produces about 12 gallons per hour. Normally a system like this will be run three to four hours per day if power is not a critical issue, in this case producing 36 to 48 gallons of water. It’s better for a system to run for a few hours every few days than an hour every day.”

cruise ro system

Watermakers for Small Boats

If space is at a premium, consider purchasing a modular system instead of an enclosed one. In a modular system, the components, such as the membranes and filters, can be mounted separately. Another power source for the high-pressure pump is the boat’s diesel engine. In these engine-driven setups , the pump and an additional pulley are mounted on a custom bracket next to the engine. The watermaker can then be run while motoring or using the engine to charge the batteries.

While engine-driven watermakers can produce a large amount of water, 20 or more gallons an hour on average, the downside is that the installation can be more complex than for other systems. “Unlike the 12-volt DC or 120-volt AC watermakers, where you simply bolt the high-pressure pump down and then run the wires and plumbing hoses, the hardest installation aspect of an engine-driven watermaker is finding space. Some boats simply have no room in the engine compartment to mount the 5-pound pump with a 7-inch pulley on the engine while still leaving access to other engine parts that need to remain serviceable,” Boren says.

rainman portable watermaker

A relative newcomer to the marine market, the portable watermaker is a good solution for cruisers who want the convenience of a watermaker but don’t want to permanently install one. The Rainman is one such system that is available as a self-contained unit driven by a gasoline-powered Honda motor, or as a 115-volt AC-powered unit. “The bulk of our gasoline-powered system customers are sailing yachts between 30 and 50 feet,” said Ron Schroeder of Rainman Desalination. “Our customers seem to prefer to have a simple and somewhat manual system over one that relies on control panels, software and solenoid valves. We are also attractive to those customers who have had bad experiences with the installation process of an installed system.”

The Spectra Passport is another portable system. Edinger said it has already proved popular with offshore race crews and cruisers who need a watermaker for only a limited time.

rainman

Maintenance for Watermakers

Watermakers have long had a reputation for being difficult to maintain, but the equipment has improved over the years and overall, routine maintenance isn’t more challenging than with other onboard systems. “The best rule of thumb is to operate the watermaker in water that looks good,” Andrews said. “There are a few factors in the feed-water condition that come into play. Operating a watermaker in dirty harbors will most certainly result in repeated pre-filter changes and a clogged sea strainer. If you have extra filters on board, you can get by, but it’s not recommended. The environment in the open ocean and remote anchorages is much better. Also consider how shallow the water is where you’re anchored. Sometimes there can be a lot of tidal movement, which can kick up fine particulate and sediment. This too can also contribute to more frequent filter changes and even damage other components. A nice option is an automatic freshwater flush, which will rinse the watermaker’s membrane element after use. It helps keep the membrane vessel housing free of any biological growth that could foul the membrane and reduce your ability to produce fresh water.”

Whatever system you choose, with proper use and maintenance you can expect years of service from your watermaker. And plenty of hot showers.

Jen Brett is a CW associate editor. This article first appeared in the February 2015 issue of Cruising World.

Aqua Marine: www.aquamarineinc.net

Blue Water Desalination: www.bluewa​terdesalination.com

Cruise RO: www.cruiserowaterandpower.com

Dometic Marine Sea Xchange: www.do​metic.com

ECHOTec: www.echotecwatermakers.com

FCI Watermakers: www.filtrationconcepts.com

Horizon Reverse Osmosis (HRO): www.hrosystems.com

Katadyn: www.katadyn.com

Rainman: www.rainmandesal.com

Sea Recovery: www.searecovery.com

Schenker Watermakers: www.schenkerwa​termakers.com

SK Watermakers: www.skwatermakers.net

Spectra Watermakers: www.spectrawater​makers.com

Village Marine Tec: www.villagemarine.com

Watermakers Inc.: www.watermakers.com

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7 Best Sailboat Watermakers For Liveaboards 2024

If you’re a liveaboard sailor looking for the best sailboat watermaker then you’ve come to the right place. In this blog post, we’ll take a look at some of the best watermakers on the market and show you how they can help make your sailing experience more enjoyable.

There’s nothing quite like the freedom of sailing on the open water. If you’re a liveaboard sailor, though, you know that keeping your boat stocked with fresh water can be a challenge. That’s where sailboat watermakers come in handy.

rainman sailboat watermakers

Not only do they produce fresh water for drinking and cooking, but they also help keep your boat clean by providing water for showers and dishes.

In this blog post, we’ll take a look at the best sailboat watermakers available on the market today. We’ll discuss the pros and cons of each model so that you can make an informed decision before purchasing one for your boat.

So, whether you’re looking for a compact unit that is easy to install or a high-performance model that can handle large volumes of water, we have something for you. Keep reading to learn more.

How do marine watermakers work?

What are the benefits of having a watermaker on your sailboat.

  • How do I choose a sailboat watermaker?

How big a water maker do I need?

How much does a sailboat watermaker cost, how much power does a watermaker use, how much space does a marine watermaker take up, maintaining your sailboat watermaker, the best sailboat watermakers for liveaboards.

As an Amazon Associate, we earn from qualifying purchases. We also earn from other affiliate programs. This means we may receive a small commission on products purchased through our links at no extra cost to you.

hands holding water

Marine watermakers are devices that convert salt water into fresh water, making them an essential tool for sailors and boaters. But how do they work?

At the heart of every marine watermaker is a reverse osmosis membrane. This is a thin, semi-permeable film that allows water molecules to pass through, but blocks out larger molecules like salt.

To create freshwater, salt water is forced through the membrane under high pressure. This process is known as reverse osmosis, and it leaves the salt behind in the brine stream. The freshwater that comes out of the other side is then collected and stored in tanks.

Marine watermakers are powered by either electricity or a diesel engine, depending on the size of the unit. Some small portable units can even be powered by a car battery.

You will probably want a pretty decent battery bank and solar or wind setup to power your watermaker. By far the easiest solution is to get a reliable, drop in battery. We highly recommend BattleBorn’s lithium batteries which is what we use to power our watermaker.

⚡ Check out BattleBorn batteries here

a tap with running water from a sailboat watermaker

If you’re thinking of outfitting your sailboat with a watermaker, you’re in for a treat. Adam and I put off buying one for two years, as we weren’t sure it would be worth the big investment. But after a year in the Cyclades where finding free town quays with water was near impossible, we decided to bite the bullet and commit.

It’s the one thing we wish we’d done sooner. A sailboat watermaker has literally changed our lives at sea and we couldn’t be without one now.

Not only will you have a reliable source of fresh water, but you’ll also be able to enjoy extended stays at sea. Here are just a few of the benefits we’ve found of having a watermaker on your sailboat:

Perhaps the most obvious benefit of having a marine watermaker is that you’ll never have to worry about running out of fresh water. Whether you’re sailing around the world or just spending a few weeks cruising the coast, a watermaker will give you the peace of mind that comes with knowing you have an unlimited supply of fresh water.

Obviously, fresh drinking water from the watermaker is great, but it also means we don’t worry about taking a shower or the huge amounts of washing up caused by certain meals or having people over for dinner!

sailboat fresh water system

In addition to providing an endless supply of fresh water, a watermaker can also help extend your cruising range. By making your own water, you won’t have to make as many stops to restock your tanks. This means you can stay out on the open water for longer periods of time and explore more distant ports. It also saves a lot of money on marinas and a lot of trips to beach showers!

Finally, having a watermaker onboard can be a real lifesaver in an emergency. If your boat is disabled and you’re stuck at sea, having a way to make fresh water can mean the difference between life and death.

How do I choose the best sailboat watermaker?

the parts of a watermaker for a sailboat

There are a few things to keep in mind when choosing a watermaker for your sailboat. There is no one size fits all when it comes to choosing the perfect watermaker for you, so take some time to read the pros and cons of each model before you commit!

a man filling up his sailboat with water

If you’re just cruising around the local waterways, you can get away with a smaller unit and top up your tanks with water from the dockside. But if you’re planning on venturing out into the open ocean, you’ll need a larger unit that can produce more water.

You’ll want to take into consideration the amount of people you’re likely to have onboard. Adam and I find out Rainman naked 12V system keeps up with our needs just fine, but after taking on two more members of crew we quickly ran out of water and struggled to keep up with the new demand.

You should also track your water usage habits for a bit to see how much water you use on a daily basis. If you can’t live without daily long showers, or you need fresh water to wash down the boat regularly, or you have fresh water flushing toilets then you’ll obviously be using a lot more water than others.

The amount of water you use when you have a watermaker is likely to increase a little from your needs now, as you’ll be a little less careful with it. Factor this into your decision!

a man running water on his sailboat

Like everything in sailing, you can spend as much or as little as you want on a watermaker. There are even some people who have successfully made their own watermaker and only spent money on the parts (some of which you can source second-hand).

If you aren’t a wizard with things like that though, you’re going to be looking at spending a decent amount of money on a sailboat watermaker. On average, they cost around £3000-£5000 for a watermaker for a cruising sailboat (around 40ft).

You can spend more like £10,000 on a watermaker for a larger boat, and you can spend less on a second-hand marine watermaker or a DIY one.

We’ve put together a guide to help you work out your needs based on what you use aboard.

Different brands of watermakers are more efficient than others, but from our own experience and that of others we’ve talked to, it takes around 10 Watt-hours to make a litre of water – i.e. about 0.8 Amp-hours from a 12-volt battery.

Things like the chemistry of your battery bank, the length of your cable runs, and even the temperature of the sea, can all make a difference to the amount of power you’ll need to make a certain amount of water, but this is a rough average.

We’ve got a guide on working out how much power you’ll need.

water bottles all lined up

A marine watermaker is a very useful tool, but it’s not exactly small. In fact, depending on the model, a watermaker can take up quite a bit of space.

The average unit is about the size of a small freezer, and some models are even larger. Given that most boats are fairly limited in terms of space, this can be a bit of a problem.

The good news is that there are now several manufacturers who offer compact watermakers that are designed to take up less space. These units are often smaller than a standard coffee maker, making them much easier to find a spot for on your boat.

We’ve included some great options for smaller boats below.

a sailboat watermaker installed in a sailing yacht

Like any piece of equipment, a watermaker requires regular maintenance. Fortunately, there are some simple steps that you can take to keep your watermaker in good working condition.

First, be sure to check the filters on a regular basis. Not only will this help to ensure that your water is clean, but it will also help to prolong the life of your watermaker.

Second, be sure to check the seals and o-rings for leaks. These are essential for keeping your watermaker operating efficiently, and any leaks can lead to costly repairs.

Finally, be sure to perform a yearly “spring cleaning” by flushing the system with fresh water.

By following these simple tips, you can keep your watermaker in good working order for years to come.

You should also account for the fact that parts are bound to break and need fixing or replacing. Most watermakers come with proprietary parts which make them a pain to fix in remote places, but there are a few that take non-proprietary parts. We would recommend these to anyone planning a larger cruising ground.

#1 Rainman naked 12V Marine Watermaker

the rainman watermaker on a sailboat

The Rainman naked 12V watermaker is a great option for anyone looking for a compact, efficient way to produce fresh water.

The unit is simple to set up and use, and it produces up to 30 litres of fresh water per hour for a smaller unit, or up to 140 litres per hour for a larger one.

One of the main reasons we were drawn to Rainman watermakers is that they use all off-the-shelf, standardised parts. If your Rainman breaks down, it almost doesn’t matter where in the world you are – you’ll likely be able to get standardised spares in the nearest major city. For any liveaboards hoping to circumnavigate this should be an important consideration.

Installation was really very straightforward. End-to-end it took two days to install and test the unit, plus an extra day to get the autoflush set up.

We were pleasantly surprised to find that the unit came with almost everything we needed to install it. We were expecting to supply our own hoses, sundries, etc. but Rainman supplies everything you need.

Whether you’re sailing around the world or just weekends on the lake, the Rainman naked 12V watermaker is a great way to ensure you have access to fresh, clean water.

Check out our full Rainman watermaker review for everything you need to know.

#2 Spectra Newport 400c Watermakers for Sailboats

Spectra watermakers have an excellent reputation among the sailing community and you can’t go wrong with one of their marine watermakers for your sailboat.

They make a range of different sailboat watermakers to suit different needs and sizes of boat, from hand-operated desalinators that can make 6 gallons a day to their largest system that produces 20,000 gallons of fresh drinking water per day.

The Newport 400c model operates on as little as 4 watts per liter, so you can run it on a small generator, solar, wind, or even just straight off the batteries. It’s a great option

The Spectra Connect system means you can operate and monitor your watermaker from a remote device, and it has lots of other clever features including a fill tank mode and suggested maintenance intervals.

You can choose the speed operation on this sailboat watermaker for maximum flow or maximum efficiency depending on your power management onboard. This is a great ‘all bells and whistles’ watermaker that takes the guesswork out.

#3 Spectra watermaker Ventura Series

As with the Newport 400c, Spectra ensure these watermakers are built to last and they have a really great reputation.

The Spectra watermaker Ventura series is designed to be energy-efficient and lightweight and is the perfect watermaker for smaller spaces.

It produces 24 litres an hour, which is less than the Rainman model but still enough for a couple living aboard a small sailboat if you’re conservative with water usage.

You can also opt for a warm water model that will produce slightly more water per hour and is the same size (but you’ll need to be sure your cruising area is only warm water!)

#4 The Ultra Whisper

The Ultra Whisper by Sea Recovery is one of the best watermakers out there for smaller boats, or boats not set up with adequate power to run one of the larger units.

It can run on either AC or DC and claims a 75% reduction in power consumption compared to the other products listed here. It’s also super quiet, which if you’ve run a watermaker before, is actually a huge bonus!

This is a small but perfectly formed piece of equipment that will enable you to make water with the smallest power setup, but obviously, on the downside, you won’t produce as much water so you’ll need to be careful with your consumption onboard.

Sea Recovery has more watermaker models on offer in a wide variety of size and capacity options. There’s even a really tiny version that measures only 2-3 cubic feet for sailboats that can’t compromise on space.

#5 Village Marine – Little Wonder series

Village Marine is another of the most popular marine watermaker brands and has a reputation for making reliable and efficient sailboat watermakers in a range of different models to suit different needs.

The Little Wonder series is one of the smallest (the reason for the name) and weighs only 69 pounds with the ability to produce 180 gallons of freshwater per day.

It has a low RPM high-pressure pump in a modular design, which means you can install it in different parts of the boat to maximise your space. This is really handy for smaller sailboats.

Installation is quick and easy, and a competent DIYer can do it. It is anti-corrosive and as a bonus, is also quiet to run!

This is one of the best watermakers on the market for smaller sailboats, and should last a long, long time.

#6 Village Marine – LW Watermaker Series for bigger boats

For anyone out there looking for a serious sailboat watermaker for a bigger boat, Village Marine has something suitable. The LW watermaker series caters to boats up to 100 feet in length.

This watermaker can produce up to 1800 gallons of freshwater a day, which is a crazy amount and will give you complete water independence on board.

It’s a much larger unit, obviously, so you’ll need to make sure you have space on board. It’s also a lot more expensive so it really is only suitable for larger boats and commercial vessels.

#7 Rainman Portable Sailboat Watermaker

Rainman portable watermakers

Rainman make a portable watermaker that has many benefits over an installed version. it won’t suit all sailboats but it’s a great option to have for the following reasons.

  • You don’t need to install the system. You can cut out a lot of the faff and make fresh drinking water within minutes of receiving the product.
  • You don’t need any extra holes in your hull to use the watermaker.
  • If you race your sailboat you can store the watermaker ashore to save on weight.
  • It’s a great option for smaller sailboats as it can be moved to accommodate for extra guests.
  • You can take it with you from boat to boat.
  • You can share the watermaker and potentially the cost!
  • You can use it for all your trips away from water supplies. Take it on road trips, fishing trips etc.

the rainman portable watermaker for smaller boats

A portable sailboat watermaker might make a lot more sense for your needs, and it’s great to have the option to choose between the two. This watermaker comes with all the benefits of the Rainman installed version, so you can check out our Rainman review to help with your decision.

Conclusion for the best sailboat watermakers

The best sailboat watermakers

If you’re in the market for a watermaker, we hope our review has helped you narrow down your choices. We believe that the best sailboat watermakers are those that are reliable, powerful enough for your needs, and easy to maintain. So if you’re looking for an efficient and durable watermaker, be sure to check out the options on this list.

If you’re looking for more liveaboard tips or want help with planning your move onto a boat then check out our ‘ How to run away to sea ‘ guidebook for everything you could possibly need to know about living on the ocean.

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29-03-2021, 21:42  
(3-4 gal) in the , and I've narrowed things down to a leak in my fresh system. I've included a drawing of my water system. My first troubleshooting step was to fill the , shut all the intake manifold valves, and then shut down the . Then let the sit for a few days. Good news there wasn't all water in the , and water gauges didn't drop so I'm assuming that water are not leaking. Maybe?

Turned on the yesterday, and opened one tank valve on the input manifold, but kept the valves on the distribution manifold turned off. Went on the today, water in the bilge and was running. However no evidence of water leaking from the , or the charcoal filter (see drawing) or anywhere else that I could see. Btw, I'm not living onboard, so I need some tricks to figure out where the leak is coming from while I'm off the boat.

Thanx  
29-03-2021, 22:01  
Boat: 1987 Pearson 39-2
when the pump is left on/ the system is pressurized.

I would NOT leave the pump on when you are not onboard. If the leak gets worse, you could end up dry pumping and ruining the pump, or worse.

Good luck. down such can be nerve wracking.
30-03-2021, 14:38  
coloring in the water. You'll see a red--or pink--depending on how much coloring you used--stain on any leaks.


--Peggie
30-03-2021, 15:50  
30-03-2021, 15:59  
Boat: Former owner of a Valiant V40
30-03-2021, 18:00  
Boat: Sayer 46' Solent rig sloop
31-03-2021, 06:21  
Boat: Hylas 49
.
31-03-2021, 06:44  
Boat: cape dory 30 MKII
31-03-2021, 08:26  
Boat: Bruce Bingham Christina 49
31-03-2021, 08:35  
Boat: Catalina 30
?
31-03-2021, 08:44  
, water, etc.) Just make sure to select the appropriate dye for the application.
31-03-2021, 09:01  
paper run it along any low spots on your hoses. When it gets wet, follow from there to the source.

Also, you can lay some TP flat on the inside of to find where the water is running from to the bilge. - Elmore Leonard








31-03-2021, 09:05  
Boat: Nauticat 43 ketch
31-03-2021, 13:36  
Boat: Tayana Vancouver 42ac
31-03-2021, 15:54  


I can't fault your logic. However, you should see pink water from a hole in the hose that water is being pushed through by the pump.


How old are the hoses? The average working life of any hose is only about 10 years 'cuz rubber and plastics dry out over time, becoming hard, brittle and prone to splitting and cracking. So if they're even close to 10 years, they might be telling you it's time to replace 'em.


--Peggie
 
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How Do Sailboats Get Fresh Water? (4 EFFECTIVE SOLUTIONS)

sailboat fresh water system

Sailors know that having access to fresh water is essential for a safe and comfortable journey out at sea. But how do they get this water? Fortunately, there are several ways for sailors to get fresh water while out at sea. In this article, well explore four effective solutions: watermakers, collecting rainwater, using jerry cans, and using a water filter. Well also discuss the benefits of having fresh water at sea and the safety precautions to take. So, if youre planning a sailing adventure, read on to find the best way to get fresh water for your trip!

Table of Contents

Short Answer

Most sailboats get their fresh water from onboard tanks that they fill up from dockside water sources.

They can also use desalination systems to take salt out of seawater and make it drinkable.

Boats that are moored in marinas may be able to get fresh water from the marina itself.

Some sailboats also have large water containers that they fill up from a hose or a freshwater source on shore.

What is a Watermaker

A watermaker is a device that is used to convert saltwater into freshwater, making it an essential tool for sailors who are out at sea for extended periods of time.

The device works by taking in saltwater, filtering it, and then using a process called reverse osmosis to extract the salt from the water.

The device then produces freshwater that is safe to drink and use for cooking.

This process helps ensure that sailors have access to freshwater even when they are far away from land.

Some watermakers are powered by a boats engine, while others are powered by an auxiliary electric motor.

In addition, many modern watermakers are equipped with advanced features such as automated operation, corrosion-resistant materials, and low-maintenance designs.

Collecting Rainwater

sailboat fresh water system

One of the most effective solutions for sailboats to get fresh water is by collecting rainwater.

Sailors can use a variety of methods to collect rainwater and store it on board.

These include using a tarp to collect rainwater, using a rainwater catchment system to collect and store large amounts of water, or using a container to collect smaller amounts.

Collecting rainwater is a great way to get fresh water without having to rely on a watermaker or other more expensive methods.

When collecting rainwater, it is important to make sure that the water is clean and free of contaminants.

Sailors can ensure this by covering the tarp or catchment area with a material such as a boat cover to keep out dirt and debris, or by using a filter to eliminate any larger particles from the collected water.

With the right setup, sailors can use rainwater to supply their fresh water needs while on board.

In addition to providing an easy and cost-effective way to get fresh water, collecting rainwater is also a great way to save on fuel costs.

Collecting rainwater requires no fuel, and can help sailors to conserve their fuel resources while at sea.

All in all, collecting rainwater is an efficient, cost-effective, and environmentally friendly way for sailboats to get fresh water.

With the right setup, sailors can easily collect and store large amounts of fresh water while on board.

Using Jerry Cans

Using jerry cans to transport water from land is a popular method for sailboats to get fresh water.

Jerry cans are large, airtight containers that are designed to withstand the harsh conditions of the sea.

They come in various sizes, and can hold up to 20 gallons of water.

This makes them ideal for sailboats, as they can be easily loaded onto the boat and transported to the open seas.

When using jerry cans, its important to ensure that the cans are properly sealed to prevent any saltwater from getting in.

Additionally, its important to check the cans regularly for signs of wear and tear.

If any cracks or holes are found, its best to replace the container as soon as possible to ensure safe and clean water.

Once the jerry cans are full of water, they can be easily loaded onto the sailboat.

This method of obtaining fresh water is great for sailors that are close to land and can easily access a source of freshwater.

Its also a great way to stock up on water for longer voyages, as the cans can be loaded up and stored on the boat until needed.

Overall, using jerry cans to transport water from land is a great way for sailboats to get fresh water.

Its a relatively simple process and can provide sailors with a reliable source of freshwater.

As long as the containers are properly sealed and checked regularly, they can provide sailors with all the fresh water they need for a successful voyage.

Using a Water Filter

sailboat fresh water system

Using a water filter is a great way for sailboats to get fresh water while they are out on the open sea.

A water filter is a device used to remove impurities from water, such as dirt, bacteria, and other contaminants.

Not only is this a cost-effective way to get fresh water, but it is also a safe and reliable option.

When using a water filter, you can either choose to attach the filter directly to the side of the boat, or you can use a portable filter.

The filter works by collecting water from a river, lake, or stream and filtering out any impurities.

The filtered water is then delivered to the boat and can be used for drinking, cooking, and other activities.

There are many different types of water filters available, depending on your needs.

Some filters are designed to remove bacteria and other contaminants, while others are designed to remove heavy metals and pesticides.

When choosing a filter, it is important to consider the type of water you will be filtering, the amount of water you will need, and the size of the filter.

One of the advantages of using a water filter is that you can filter water from any source, making it a great option for sailboats.

Additionally, water filters do not require a large amount of electricity, making them an ideal choice for sailboats.

Not only is it cost-effective, but it is also safe and reliable.

With a variety of filters available, you can be sure to find a filter that meets your needs.

Desalinators

When it comes to getting fresh water while sailing, desalinators are one of the most reliable and effective solutions.

A desalinator is a machine that converts seawater into fresh water.

It works by using a process called reverse osmosis, which filters out salt and other impurities from the seawater and produces freshwater as a result.

Desalinators can be powered by electricity, or they can be powered by the boats engine, making them flexible and convenient.

Desalinators are often used in boats that are sailing in areas with limited access to freshwater sources, such as the ocean.

They are also often used in emergency situations, as they can provide a reliable and safe supply of freshwater in the absence of other options.

Desalinators are also typically more efficient than other methods of obtaining freshwater.

They use a relatively small amount of energy to produce a large amount of freshwater, making them cost-effective and efficient.

Additionally, they require minimal maintenance, making them a great option for sailors who want a reliable source of freshwater while at sea.

The only downside to desalinators is that they can be expensive to purchase and install.

However, if you are a sailor who needs a reliable and consistent source of freshwater while sailing, a desalinator is likely your best bet.

Benefits of Fresh Water at Sea

sailboat fresh water system

Having access to fresh water while sailing at sea is essential for the safety and comfort of the crew aboard.

Not only does fresh water provide the essential hydration needed to sustain life, but it also helps to keep the boat and its occupants clean and healthy.

Fresh water can be used for cooking, washing dishes, showering, and laundry, and it can also be used to replenish drinking water supplies.

Having access to fresh water also helps to reduce the risk of dehydration and other health risks associated with drinking saltwater.

Finally, having access to fresh water can help to reduce the risk of running out of supplies while out at sea, as fresh water can be used to refill drinking water tanks and other vessels.

Safety Precautions

When it comes to getting fresh water for a sailboat, it is important to take safety precautions.

This is especially true when dealing with water from rivers, streams, or lakes, as these sources may contain harmful bacteria or other contaminants.

It is also important to practice safe water storage and transportation techniques when collecting water from jerry cans.

Boats should also be equipped with the necessary safety equipment, such as life rafts and life jackets, in case of emergencies.

Additionally, boat owners should make sure that their boat is properly equipped with all necessary navigation and communication equipment, as well as the necessary safety gear.

Finally, all crew members should be trained in how to properly handle and store the water they collect.

This will ensure that everyone is safe and that the water is handled with the utmost care.

Final Thoughts

Having access to fresh water while at sea is essential for a successful sailing journey.

All of the solutions discussed here have their own advantages and disadvantages, so it’s important to assess your situation and choose the best option for you.

Whether you choose to use a watermaker, collect rainwater, use jerry cans, use a water filter, or employ desalinators, you’ll be able to ensure that you have the fresh water you need to stay safe and comfortable while sailing.

James Frami

At the age of 15, he and four other friends from his neighborhood constructed their first boat. He has been sailing for almost 30 years and has a wealth of knowledge that he wants to share with others.

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The Care And Feeding Of Your Boat's Water Systems

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Boating is all about water, inside and outside your boat. Let's take a close look at important maintenance tasks to stay on top of all your water systems.

Boat water system illustration

Illustration: Dick Everitt

  • Anchor/foredeck washdown with pressure pump and foot switch
  • Galley sink. Filter for cleaner cold water. Sink drains above waterline at max heel. All thru-hulls must comply with ABYC standards
  • Condensation drip tray drains overboard above waterline at max heel per ABYC standards
  • Icemaker door open when not used
  • Bilge pump drain well above water line on max heel. Smooth inner lining to hose. Vented loop may be needed if drain is near or below water line at max heel
  • Head sink with filter on cold water and drain above waterline at max heel
  • Shower sump pumped overboard to discharge above water line at max heel. Shower drain hose goes to shower evacuation pump. Head intake hose has a strainer and thru-hull
  • All thru-hulls equipped with seacocks. Note double hose clamps
  • Holding tank vented with minimum bends for better airflow
  • Head discharges to MSD Type 1 with Y-valve
  • Holding tank has pumpout hose and gravity discharge overboard after treatment where it's legal
  • Water heater has anti-backflow valve to prevent expanding hot water from entering cold water system (This tank is shown lying on its side, an installation seen on some boats. Normally, hot-water tanks are upright.)
  • Anti-siphon loops and valves where appropriate
  • Potable water tank with fill and vent
  • Potable water tank has sediment filter prior to pressure pump
  • Accumulation tank diminishes pulsation
  • Scuppers drain cockpit. Some boats need scuppers with hose to discharge

Seawater Washing (1) — Seawater systems such as anchor washdown and dishwashing with a seawater foot pump (if you're in clean water and rinse well with potable water) can conserve water. Frequently bathing in saltwater causes skin problems in many people; a freshwater rinse helps. Washdown water pump should be a short distance from the thru-hull but above the waterline.

Drinking Water Purity (2, 6) — When in question, can be improved by adding a small amount of bleach. Some authorities recommend adding approximately 1 teaspoon of household bleach with no perfumes, dyes, or other additives per 10 gallons of water. If possible, agitate the water after adding bleach and then let it sit for an hour. Chlorine odor will dissipate after a day. Bleach may initially make the water to which it's added unclear because it's killed the “bugs.” The water clears as these settle to the bottom. Ultimately they should be flushed out. It's preferable and safer to add product manufactured for the purpose; camping stores are good sources. If you have questionable water purity and no way to remedy it, boil water before drinking. Drinking-water filters such as GE's FXUVC under-the-sink cartridge remove many impurities and greatly improve taste. A water system UV light, such as those used in some reverse-osmosis systems, can kill viruses.

Air Conditioning & Refrigeration (3) — Condensation drain trays should occasionally be inspected to clear any blockage in drain hoses, which should preferably drain overboard rather than into the bilge. If trays don't drain fully, they'll develop a musty odor that will be circulated by the air handler.

Icemakers (4) — Should be left open and off when not being used for a few days or longer to avoid odor and mold. Often the incoming water line is behind the unit in an area warmed by the unit. This facilitates stagnation and odor, particularly in the filter that may be in that area. When in use, the ice bin should be dumped at least every few days to keep water flowing. Good ventilation helps.

Bilge Water (5) — Oil-absorbent pads in bilges under the engine and whenever there's oil-spill potential are critical. They must not interfere with the operation of a bilge-pump float switch. Always clean loose fuel and oils out of the bilge with an oil-absorbent pad, and discard appropriately. Proper bilge-pump installation is critical and will vary with different boats. The hose interior should be smooth, the water column in the hose should be no more than needed, and great care must be taken to avoid backflooding from the sea. Visual and audible alarms at the helm are crucial.

Bilge pump hose should exit well above water line at maximum heel within the parameters of ABYC standards. Pumps should be in sections where water can pool more than minimally.

Basic bilge pump schematic

A basic bilge pump schematic.

Sumps (7) — Those used for showers should be cleaned and flushed through regularly, even if the shower isn't often used. Shower sumps should discharge well above the water line at maximum heel within the parameters of ABYC standards.

Thru-Hulls (8) — Should be checked for obstruction every time you haul the boat and/or dive the bottom. Inspect them with a strong light, such as Streamlight's Stylus Pro 360 , while hauled. While in the water, you may need to carefully (to avoid damaging hose and valve) work an old table knife or similar tool around inside the hole to clear it of barnacles and other obstructions. A carrot peeler makes a good tool for small holes. If the hole is covered by an external filter, this should be removed, when hauled, for painting inside, inspection, and cleaning.

Seacock illustration

Water Passages (8, 6) from thru-hull openings — Sinks, heads, engines, air conditioners, refrigeration, bilge pumps, and other components use thru-hull openings and hoses. Regularly inspect and operate all thru-hull valves . Some valves periodically require disassembly and lubrication or cleaning while the boat is hauled. You may need to close one quickly when a breach occurs in a water passage inside the boat.

Regularly inspect all hoses and connections . Old or suspect hoses will deteriorate over time and should be replaced. Eventually, wire inserts will rust and harm inner and/or outer hose walls. Preferred hose clamps are AWAB brand or similar. Double the clamps (unless doing so would cut into the hose, in which event a longer hose barb is indicated) and regularly inspect.

All components should be 316 grade stainless or better. Cheap hose clamps tend to rust and break. Use hose appropriate for the job, such as marine-sanitation hoses for heads. ABYC standards should be followed in these and all other aspects.

Holding Tank (9, 10, 11) — Some chemicals added to holding tanks can harm the environment if spilled, either from the boat or from pumpout-disposal systems and system failures. Various companies market what they claim to be environmentally friendly holding-tank additives with varying degrees of effectiveness. Some boaters install a Raritan ElectroScan MSD plumbed to treat and discharge overboard where it's legal, and treat and discharge into the holding tank at other times.

Head Water (10) — Regular addition of products such as Star brite Instant Fresh Toilet Treatment and Raritan CP help keep head water odorless and improve operation of the head . Petroleum-based products can harm valves, seals, and gaskets. Check manufacturer's recommendations. Regularly pouring white vinegar into the head and flushing will help diminish calcium buildup on inside walls of head plumbing. Raritan's CH is stated to be environmentally harmless and is specially formulated to remove heavy calcium buildup as well as prevent buildup if used regularly.

Head discharge hoses should be specified for MSD use. Other types of hoses are usually more likely to develop calcium buildup, deposits, blockages, and odor permeation. Plumbing the head to flush with fresh water can reduce odor. The head intake hose is positioned as it is in the illustration for clarity, but should be far enough from the head discharge to avoid sucking up waste.

Water Heater (12) — Should be standing upright with a backflow valve between the incoming cold water and the heater. Requires periodic flushing by squirting in clean dock water with a water hose under moderate pressure through a discharge port at top, squirting around inside as much as practical, and draining through open intake port at bottom. Some water heaters have an anode for cathodic protection that should be checked yearly.

Vented loop illustration

Anti-Siphon Loops and Valves (13) — Are needed in some hoses that exit underwater to prevent water from siphoning into the boat. Whether anti-siphon valves and loops are used depends in part on the location of relevant components in the boat and whether they're below the waterline or could end up below the waterline. These components may include heads, sinks, and engines and their raw-water intake and exhaust systems. As a precaution, when you're away from your boat, close the underwater seacocks.

Potable Water Tank (14, 15, 16) — Should be treated periodically with a product such as Star brite AQUA Water Treatment & Freshener to remove odors, scale, and bad taste. Also, thoroughly flush tank with clean water and pressure nozzle. Drain from bottom if possible; if not, pump it out. Follow manufacturer directions when applying anything to drinking water.

Follow instructions and warnings for cleaning additives, particularly with aluminum tanks. New tanks, especially fiberglass or plastic, may smell of the material of which they're made. Often, adding baking soda to the water will help, as well as with other odors later. The amount depends on the severity of the problem and volume of the tank.

Clarity of water may vary with source, such as from wells, cisterns, public water works, and reverse osmosis. The latter source, if coupled with a UV light and maintained well, probably produces the best water.

Drains and Scuppers (17) — Cockpits, side decks, and other areas of a boat normally have drains to rid the boat of rain and boarding seas. Test these regularly with a hose to be sure they're draining adequately. Leaves, plant material, dirt, and other debris can quickly obstruct them. Boats can sink if drains aren't kept clear. Clear them with a high-pressure hose nozzle or plunger.

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Fresh Water System

  • Thread starter kiteflyer
  • Start date Jun 23, 2018
  • Hunter Owner Forums
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kiteflyer

Looking for advice on my fresh water system. My 1991 Hunter 28 is a great boat that I sail a lot but never use the water system. I filled it a year ago just to test it out, and while the pump worked fine, I couldn't get any hot water. Could somebody give me a primer on how the whole system works or point me to some resources? Also, I just can't figure out how to turn on the shower head (OEM shower). Thx.  

Kings Gambit

Kings Gambit

kiteflyer said: Looking for advice on my fresh water system. My 1991 Hunter 28 is a great boat that I sail a lot but never use the water system. I filled it a year ago just to test it out, and while the pump worked fine, I couldn't get any hot water. Could somebody give me a primer on how the whole system works or point me to some resources? Also, I just can't figure out how to turn on the shower head (OEM shower). Thx. Click to expand

There is a switch on my AC side - Water heater. I expected that it would heat pretty fast, but it didn't. do I have to have the engine running for the whole system to work? I guess I thought that with the pump switch on and the water heater on I wouldn't have to be running the engine.  

I also cleaned out a half-liter or so of yellow antifreeze from my pan this morning. Am I right that the anti-freeze circulating through the system is what heats the freshwater system if my electric heater is off?  

kiteflyer said: There is a switch on my AC side - Water heater. I expected that it would heat pretty fast, but it didn't. do I have to have the engine running for the whole system to work? I guess I thought that with the pump switch on and the water heater on I wouldn't have to be running the engine. Click to expand
kiteflyer said: I also cleaned out a half-liter or so of yellow antifreeze from my pan this morning. Am I right that the anti-freeze circulating through the system is what heats the freshwater system if my electric heater is off? Click to expand

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sailboat fresh water system

the diagram is correct. however, there should be cut off valves on the hoses between the engine and the heater. if the heater were to fail. and they do. then you can isolate the engine from the heater and still run the engine. look for such valves.  

MikeHoncho

If the heaters AC breaker was turned on with the tank dry (fresh water side) it will burn out the heating element. Check ohms of the element to see if it is open ( 0 ohms) which would mean this is the case with yours.  

Hello Below

Hello Below

MikeHoncho said: Check ohms of the element to see if it is open ( 0 ohms) which would mean this is the case with yours. Click to expand

Which is irrelevant when talking about a cheap meter checking the massive resistance of a good (working) heating element compared to a bad one.  

MikeHoncho said: Which is irrelevant when talking about a cheap meter checking the massive resistance of a good (working) heating element compared to a bad one. Click to expand

I'm attempting to be as basic as possible..... research the ohms for a good element for your heater. If the old one is lower than spec, 0 or --- then replace it. If it is close or on spec then it is more than likely a different issue.  

Panera

There is normally a bypass on the water heater which is normally used during winter storage. Check to see if the valves are adjusted to bypass the heater core.  

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How To Clean Your Boat's Freshwater Tank (Plastic & Aluminum)

Cleaning the fresh water tank in your boat is one of the most essential things you should do regularly to ensure smooth sailing. You need safe and clean water onboard to drink, bath, cook and clean. This can only be achieved by maintaining a clean water system. Today, I will guide you step by step on how to clean your freshwater tank, both plastic, and aluminum.

How to clean your boat's freshwater tank:

  • Drain the tank completely
  • Measure 1 teaspoon/gallon of household bleach (aluminum) or vinegar (plastic) into the tank and add fresh water until it’s full
  • Let it sit for 24 hours to sterilize, then drain the water
  • Fill with fresh water and drain repeatedly until all the bleach/vinegar odor is gone

This job should take you anywhere from 5-10 hours.

After this process, your tank should be clean and safe to put in fresh water for use. The problem is that sometimes your tank needs more than this method to be clean. Continue reading to find out how you can leave your tank sparkling clean.

Dirty freshwater tank with black streaks and grass

On this page:

How to ensure the water tank is uncontaminated and squeaky-clean, the freshwater tank refill, filtering and sterilizing the incoming water, related questions.

Sanitizing your fresh water tank will greatly help in removing the strange odor and bad taste of the water onboard. It will greatly reduce the occurrence of coliform bacteria and will ensure the health of everyone onboard.

Fortunately, keeping the water tank in a better condition to provide good-tasting and drinkable water is very easy.

To start with , check if there’s detritus accumulation on the tank. You can do this from the equipped with inspection and cleaning ports on the tank.

To check , put on a sanitary glove and swab inside the tank with your finger. If it’s slimy or emits an odor, your tanks should be cleaned with detergent and sanitized.

If you haven’t cleaned your water tanks properly in a long time, you might find a thick even stubborn crud layer in the bottom.

Even though removing the tank out of the boat and steam-clean it works great, many of the times it’s not practical. For tough cases though, you should probably steam clean them.

Otherwise, you can use the following steps:

  • Empty all the water in the tank
  • Add a few inches of ice cubes in the tank
  • Add a small amount of water for the cubes to slide the bottom of the tank
  • Take the boat in a place with wave action for the cubes to slosh on the bottom of the tank. - The cubes will scrub the bottom as they melt
  • Remove the water filters to avoid the clogging and then flash the tank until everything is clear
  • Make sure you flush with clean water to avoid sanitizing again later

What to Use to Clean Water Tanks?

  • For the first rinse, steam cleaning is the most effective way. If your tank is in bad shape, steam cleaning is the way to go.
  • If you don't have a steam cleaner, use a pressure washer instead.
  • For steel and aluminum tanks , you can use bleach to flush the system.
  • For plastic tanks , you can use vinegar or lemon.
  • You can also get a special Water Tank Flush, which works well, but is more expensive.

This last one works surprisingly well. The organic acids will dissolve any debris. Vinegar, however, won't leave any odors.

Some tips on using bleach

Plastic tanks may retain chlorine flavor, so I'd recommend trying to use vinegar before trying anything else. Also, if you're using bleach, I would disconnect all the outlets. If it gets into your lines, your water will taste like chlorine for a while. It doesn't hurt, but it doesn't taste nice either.

After cleaning the tank from the buildup, it’s time for sanitizing the water system: “System” because it does no good to clean the tank and leave the pump, lines, and others.

You can sanitize the system by adding home bleach 1 teaspoon per gallon or precisely 8 ounces per 10 gallons of the water in the tank.

CAUTION : This bleach is to sanitize the system, it’s not fit for drinking!

Pressurize the water with the system open but turn off the end outlets. Let it sit for 24 hours;

After that flash the water with each outlet starting with the furthest from the pump. Do this with all the outlet and repeat the flush until all the bleach smell is gone.

Warning : for Aluminum tanks, you should not sit the bleach for more than 24 hours. Also, you should not repeat this process for more than twice a year.

At this point, the system is clean and sanitized. It’s now time to fill the water tank with fresh water from different sources; you can get from outside sources or use the onboard water maker to refill the tank (water from the onboard maker is often sterile and pure).

If the water is coming from outside source however you must take extra caution. For starters, make sure the fill cap is in good condition to avoid water leaks into the tank with contaminants. It makes no sense to clean the tank and put in contaminated water from outside.

Ensure the hose pipe that you are using to fill in your tank is FDA rated to use for potable water. Also, before you put it directly into your tank, let the water run first to flush the hose. Understand: a hose with water in the sun can be a home to many living organisms.

Note: A better solution is to have your own horse which you flush after use and store safely.

Also running water will help you to know the condition of the water from the source. If the water looks dirty, don’t fill in your tank with it. It might be contaminated with things like cyst, bacteria or even metals, there is no need to take chances.

Tip: the key to having clean water onboard is usage. Keep the water flowing in and out of the system regularly to reduce the chance of it becoming stale.

IF you are getting water from an outside source that you are unsure of its safety, you must take extra caution to make sure you are getting quality and clean water. You can guarantee this if you use sterilizers and filters.

When buying a water filter, make sure that it has met all the Microbiological Purification Standards. With this, you can eliminate all the cysts, viruses and bacteria from the water.

Alternatively, go for an Ultraviolet Sterilizers. With this, the water is sterilized by UV lamp that produces UV radiation to kill bacteria.

In addition, add a filter to remove other contaminants.

Chemical water treatment

A good alternative to treat the onboard fresh water in the tanks is by use of chemical products. There are different varieties you can find out there although you be cautious to read on the label because different products have different usage. You might find some that just remove the smell and taste of the water while other sterilizes the water to make it bacteria free.

Often, Iodine and Chlorine based products are better solutions to make questionable water safe to use. If this is not available, use home bleach; ½ teaspoon for 5 gallons and let it sit for 30-60 minute and it will be good to drink.

Checking if the water is safe for use

The best way to determine if the water in the tank is safe for use is to have it tested. Visit a local lab. if you don’t know any visit your local health department and they will direct you.

This method though is only valid only for the water in the tank. Alternatively, purchase a self-testing kit, which although they are not as accurate they can indicate if there is a problem with the water.

How to empty holding the tank on the boat? There are two ways that you can empty the holding tank; one, go at least three miles offshore and empty the tank there or go to a fuel dock with a Marine Sanitation Device (MSD) and a waste pump to empty it for you.

How to install a freshwater tank on a boat? The freshwater tank should be installed close to the middle of the boat. Have a small water pump and enough hose. Get the measurement where the hose should run and fit it. Add a T connection to the pickup line on the pump and run one hose into the tank and the other outside of the boat. Next cut the drainage outlet, place the tank to the selected location and fix everything tight and the tank is ready for use.

How to prime a fresh water pump on a boat? To prime water pump on your boat, start by ensuring there is enough water in your tank then checking the filters and screens to make sure they are working alright. Next opening an outlet like the facet to let the air out and it will prime.

Pinterest image for How To Clean Your Boat's Freshwater Tank (Plastic & Aluminum)

John Robbins

One teaspoon in 1/6 of an ounce. One teaspoon per gallon is 1.67 ounces for 10 gallons, not 8 ounces! That is way too much bleach.

Elina Brooks

Thank you for letting us know that steam cleaning is the most effective way to clean a fuel tank, especially if it’s in a bad shape. My dad owns a fishing boat, and he was thinking of getting a new fuel tank for it soon. I’ll be sure to tell him about this before he gets a custom order for his aluminum fuel tank soon. https://www.mycarrenterprise.com/boat-fuel-tank

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Rainman Portable Water Maker

Why portable.

The origins of Rainman established our reputation as the “Portable Watermaker” in the blue case. Although many customers will prefer to install their Rainman, many benefits exist for keeping your system portable.

  • You don’t need to install the system. Ten minutes after receiving the system, you can be making fresh drinking water.
  • If you are a cruiser and a racer, you can easily offload about 2/3 of a crew member in weight by putting the watermaker ashore.
  • No extra holes in your hull.
  • If you are space constrained, you can remove the system for more people and gear on shorter trips.
  • If maintenance is required, you bring the system to a technician rather than a technician to your boat.
  • When you upgrade your boat, the system goes with you. Installing a system in your boat will not add much value to your boat.
  • You can loan it to a friend.
  • Reduced initial cost due to no expensive installation process.
  • You can fill up your neighbour’s tanks with our product water extension hose.
  • Moving the system around is easy if you have an RV, live near water, or have another boat.
  • You can easily resell the system if you are no longer getting use out.
  • Minimise risk to your vessel during storm season by leaving your Rainman ashore.

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System Types Available

You have maximum flexibility in power sources if you wish to keep your system portable. Any of our three platforms can be used as portable. In order of popularity, these include:

AC powered watermaker The primary design principle in the AC Rainman is that it must start and run using a Honda 2kVA portable generator. The ubiquity of this generator has helped make it the most popular system in our range. It can also run on a good quality 2kVA inverter. Higher capacity generators and inverters are commonly used as well.

Petrol (gasoline) powered watermaker   An update of the original Rainman, this system can run without any external electricity source. Just add fuel and salt water. We designed this with a Honda GXH50 motor and a simple belt drive system.

12-volt DC powered watermaker This system was designed with lower power and lower flow rates. Simplicity and low maintenance is retained by utilising a simple triplex plunger pump. Due to the lower productivity and requirement for a shorter power cord, this system is more commonly installed than kept portable.

Rainman Watermaker Family

Two Components – One Watermaker

The system is made up of a pressure supply unit (PSU) and a reverse osmosis unit (RO). Both parts are required to make a complete watermaker. The PSU lifts the seawater, filters out the sediment and puts the system under high pressure, while the RO unit extracts fresh water from the stream of pressurised seawater. Most of the water goes out to waste as brine output, while about 20% of the volume is extracted as fresh potable water for your tanks. Different RO options exist for you to select with your AC Rainman system, each to achieve their own specific objective.

installed petrol watermaker

Flexibility for the Future

If you are uncertain whether you wish to have a portable or installed watermaker, the best option is to buy the portable version. You can then run it portable for a while and decide if you are happy with that configuration or wish to install it at a later date. It also gives you more time to determine where you want to install the system. Analogous to buying a pre-owned house, you live in it for a while before deciding what renovations you might require. It is easy to install a portable watermaker, but you do not want to uninstall a permanently mounted system.

watermaker for yacht

Using the Watermaker

After a few uses, it will take about two minutes to set up your watermaker for use. More detail is available in the operations manual, but the steps are:

  • Set the systems up. You may choose to leave the systems in a locker and only move the hoses around.
  • Hook the black high pressure hose from the reverse osmosis case (RO) into the quick connect coupling on the pressure supply unit (PSU).
  • Put the intake hose into seawater.
  • Put the green waste brine hose overboard.
  • Turn the system on.
  • Slowly pressurise the system to 55 bar (800 psi) using the control valve. Fresh water will begin coming out of the white product water hose.
  • Let it run for a short period of time, then put it in your tank.
  • When tank is full, depressurise the system and put it away.

how to use watermaker

Maintenance Requirements

While there is limited maintenance on your Rainman watermaker, there are a few things that should be looked after to ensure a long life of your system.

When storing system:

  • Fresh water flush and pickle the system when storing it for more than a couple days. This may sound complex, but it is an easy five minute process with no specialist knowledge required.

5-50+ hours of use:

  • Change the non-proprietary prefilter after 5-50+ hours of us, depending on cleanliness of the source water.
  • Change non-proprietary impeller in the lift pump after a year or two, depending on use.
  • Change the high pressure pump oil each 300 hours of use, using SAE-30 weight oil.

5-10 years:

  • Change the non-proprietary sized reverse osmosis membranes after 5-10 years.
  • If your system starts losing performance, the non-proprietary pump seals may eventually require replacing.

watermaker for yacht

Spares and Consumables

Your new Rainman system will arrive with enough spares and consumables to keep you going for a while, so most customers do not need to order more with initial purchase. There are a variety of items you will need over time to keep your system running for many years.

» Rainman Watermaker spare parts and consumables

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About Fresh Water Boat Systems

Keeping your water fresh with a high quality boat systems.

Fresh Water Boat Systems is primarily for boats that have the capacity to store and move fresh water, usually for at a sink or shower in the cabin. In addition to the water pressure pumps required for a fresh water system, we offer things like water tanks and heaters, sinks, showers, pressure regulators, and chemical treatments. Brands such as Jabsco, Whale, Raritan, Flojet and Scandvik have put in the time and energy to make sure their products are of the highest quality, and designed to deal with a constantly wet environment.

Fresh Water Boat Systems How-Tos

How to install a shower pump on my boat.

After a hot day out sailing, racing, fishing, or simply relaxing on the deck, a boater always looks forward to a refreshing shower. Nothing beats the feeling of powerful water jets splashing on your body. However, due to structural and space limitations, it can be a bit challenging to get the right water pressure. This will particularly affect small watercrafts. In order to make certain the shower works just right, it is necessary to put in place a good boat shower pump. This device is charged with making sure there is a constant flow of water. It also helps in maintaining consistent water pressure thus offering you a "power shower."

Why is a shower pump needed in a boat?

As a boater, you may be asking if it's necessary to have a shower on a boat. Well, if you desire to get rid of the salt, dirt, smell or sweat from your body, then you need a shower and a water pump. Unlike a home, a boat will have a little area to hold the water. This simply means that you have to work with limited quantities. In addition, the water tanks will be located below the deck or on a slightly raised platform. Therefore, the pressure of water will be low. A pump increases the water pressure and also reduces wastage and keeps you clean.

Installing a Boat Shower Pump

  • Shower pump
  • Wood or Rubber slab
  • Power Drill
  • 15-mm Pipes
  • 25 Amp fuse
  • Screwdriver
  • Screws/Bolts

Instructions

  • Identify a good spot on the boat. It should be kept as near as possible to the tanks storing water. It is always a good idea to position the pump at a point that is lower than the water tank base (bottom).
  • Position the pump on the wood or rubber piece and mark the holes. Do the same to the desired area on the boat.
  • Take the power drill and drill the holes on the slab as well as the boat.
  • Align the slab on the boat and place the pump horizontally on top of the slab.
  • Insert the screws or bolts and attach the nuts underneath. Tighten with a screwdriver or wrench.
  • Connect the pipe from the water tank to the inlet side of the filter. Another pipe should be connected from the filter's outlet to the inlet of the pump.
  • Connect another pipe from the pumps outlet to the shower. You may also place a filter between the pump and shower head.
  • Locate the pump's positive (red) wire and splice it to a positive power source in the fuse box. Place a 25 amp fuse while making sure power has been disconnected or switched off. Connect the other black (negative) wire to a negative point.

Tips to Choosing a Boat Shower Pump

Choosing the right shower pump comes with its fair of challenges. This is fueled by intense market rivalry, lack of knowledge, a wide range of products, and more.

The following tips will come handy when thinking of fitting a shower pump:

Frequency of Use: - If the shower only serves one or two people, or is used rarely, then a small or medium pump should be sufficient.

Pump Output: - The pumping pressure is usually between 1.0 to 4.5 bars. Too much pressure may affect power consumption and also other constituent parts such as the shower heads and pipes.

Energy efficiency: - A good pump should provide maximum pressure with minimal usage of power. It makes no sense to install a large and powerful pump if one or two people will be using it.

Brand Reputation: - Shower pumps come in varied designs, shapes and brands. Always go for a brand that is known to be durable, energy-efficient, cost-effective and easy to install.

Many boaters or boat owners have the notion that installing a shower pump in the boat is a laborious activity. In fact, some will choose to splash water on themselves while others will stick to the faulty shower. Well, this doesn't have to be the case. Replacing or installing a shower pump can be undertaken by any person with basic skills. No extensive knowledge on plumbing or wiring is required. The whole exercise may require only a few hours hence you can decide to set aside one sunny afternoon to carry out the boat shower pump installation. You can turn the activity into a pass time by asking a friend to assist. Before you install a pump, be sure to browse through our high quality pumps to ensure you get the best pump at a great price.

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5 Best Watermakers for Sailboats

Last Updated by Daniel Wade, October 1, 2021

sailboat fresh water system

With the right Watermaker, the ocean becomes an almost immeasurable supply of fresh and clean drinking water to keep you hydrated during your offshore sailing adventures.

Many sailors do spend a lot of their time and money on various parts of the sailboat including the sails, engine, electronics, and generators especially when preparing for long-distance voyages.

While there's absolutely nothing wrong with this, they often overlook one crucial part of general human survival: having an ample supply of fresh drinking water.

Whether you have freshwater drinking tanks on your sailboat or planning to cruise in areas where you can easily access clean drinking water, the hassle involved in having to come to the dock to fill the water tanks can be quite overwhelming.

This is exactly why you need to find the best watermakers for sailboats.

Like many other nautical technologies, watermakers have significantly advanced in the last few decades to become very efficient and more reliable. They're no longer a luxury on your sailboat but a necessity. Better still, watermakers have become relatively affordable and are meant to keep you hydrated as you explore areas that do not have clean and fresh drinking water.

In this article, we'll take a look at how watermaker systems work, highlight their benefits, and highlight the best sailboat watermakers on the market right now. At the end of this read, you should be able to choose the best watermaker for your sailboat.

Benefits of Having a Watermaker on Your Sailboat

The freedom and security that come with having full water tanks on your sailboat are of immense importance, especially if you're cruising in an area where fresh drinking water is hard to come by and quite expensive when you do. As such, having a watermaker aboard your sailboat is no longer a luxury like it used to be in the past. With a steady supply of fresh and clean water, your life on the sailboat will be a lot better. This is because you'll have enough clean water to drink, cook, wash, and shower, which is beneficial if you want to enjoy your sailing adventures.

Honestly speaking, many sailors do not actually need a watermaker. Well, if you're planning to sail just near the shores, then there's a chance that you can easily access fresh and clean water by the dock. But this can be limiting if you've been dreaming of going off the grid and sailing to some exotic and unknown places in the world.

With that in mind, a watermaker makes a lot of sense to most sailors. You won't have to worry about having to carry aboard gallons of freshwater for cooking and drinking during your voyage. You won't have to treat freshwater as a precious commodity that must last until you can refill at the next port. With a watermaker, you can simply go ocean crossing without worrying about running out of water.

A watermaker allows you to have a steady supply of fresh and clean water to keep everybody well-hydrated and healthy. You can clean the water anytime you feel like and all you have to do is replace the filter once in a while and you'll be good to go. In essence, a watermaker is probably one of the most important equipment to have aboard your sailboat, so installing it is of great importance if you're a serious sailor.

The Basics of Modern Marine Watermakers

Modern marine watermakers essentially follow the principle of reverse-osmosis to produce pure, drinking water from seawater. During this process and through very high pressure, seawater is forced through a semipermeable membrane that only allows freshwater molecules to pass through it but not salt, bacteria, or any other organic material. The newly made pure, drinking water is then piped to the sailboat's water tanks while the leftover (brine) is discharged overboard.

Even though marine watermakers may differ in the type of pump that's employed and how it is driven, this is one of the most important features in every watermaker. In most cases, water can be electrically pumped or powered directly off the boat's engine. If you have an AC generator or alternator on your boat, it would make much sense to use the AC output to drive the watermaker directly. You can also choose the DC-powered models if you rely on renewable energy from solar or wind. Alternatively, you can still go for AC-powered watermakers but you'll have to buy an inverter.

All in all, DC-powered watermakers are more efficient since they integrate a power-saving energy recovery system (ERS). You must, however, keep in mind that your energy consumption levels might be quite high if you're sailing in colder and saltier areas. This is because the water purification process might be a bit slower in such areas. As such, you should consider investing in a more high-powered watermaker system if you will be sailing in colder and saltier areas than if you're planning to sail more in warm and less salty areas.

As far as an engine-driven watermaker is concerned, you should mount the high-pressure pump on the engine so that it can be belt-driven using an automatic clutch. An engine-driven watermaker should be your first option if you want large quantities of fresh drinking water. This is more productive than AC or DC-powered watermakers. Even with a relatively small engine, this setup has an automatic regulator that constantly pumps the water. With that in mind, engine-driven watermakers are ideal if you want to reduce your energy consumption. To put it into perspective, an engine-driven watermaker can lower energy consumption by an enormous 80%, especially when compared with conventional AC or DC-powered watermaker systems.

How to Choose the Best Watermaker for Your Sailboat

There are many factors to consider when looking for the best watermakers for your sailboat. Here are the most important things to consider.

Your Freshwater Needs

One of the most important things to consider before spending your money on a watermaker is your freshwater needs. What quantity would be enough to keep you going on your sailing adventure? While the quantity might differ from one sailor to the other or from one boat to the other, you should consider the number of gallons that a particular watermaker can produce per day. This will help you in choosing the ideal watermaker; a model that will ensure that you never run out of water. Do not underestimate your water needs, especially if you're planning to sail with your children or if you're planning to stay on the boat for an extended period of time.

Do you have enough space on your vessel to accommodate the type of watermaker you're looking to buy? While most watermakers are designed to fit in the smallest of space, you should consider the actual size of the watermaker and find out whether you have enough space on your vessel to fix it.

Watermakers can run on electricity, renewable energy such as wind and solar (if you have them on your vessel), or both. When looking for the perfect watermaker, you should consider how to power it and whether or not the watermaker has low-energy consumption, which is definitely a great feature. Again, there are also engine-driven watermakers, so it's important to know exactly what you're going for.

Maintenance

Watermakers have a reputation for being difficult to maintain. Fortunately, the equipment and components have improved in the last few years so you should go for a model that's easy to maintain. You should use the watermaker in water bodies that look good, You should avoid using the watermaker in dirty harbors as you may have to change the filters every so often or even damage your watermaker altogether.

Best Watermakers for Sailboats

Let's take a look at the best watermakers available on the market right now.

The Ultra Whisper

sailboat fresh water system

Engineered by limited electrical options that can run on either DC or AC, THE Ultra Whisper by Sea Recovery is one of the best watermakers currently available on the market. In addition to being very quiet, this watermaker features an automatic operation that requires very minimal operator adjustment.

This watermaker is ideal for small powerboats and sailboats since it can serve as an efficient water supply. This model boasts about a 75% reduction in power consumption, especially when compared to other models.

‍Smooth and quiet water production

Can produce up to 2,280 liters per day

Ideal for small boats

It is energy efficient

‍It might not be perfect for large boats

Echotec Watermaker

sailboat fresh water system

If you want a watermaker model that can produce 60 liters per hour flawlessly and with no maintenance apart from changing the filters, look no further than the Echotec Watermaker. This model is designed for ultra-reliable performance and easy customer installation.

This watermaker is made from high-quality components that can withstand the continuous harsh marine environment, making it one of the most durable watermakers on the market. This is essentially a series of modular watermakers ranging from 12-volt to 24-volt DC-powered models. They bring forth energy efficiency, a computerized energy recovery system, and ultimate reliability to ensure that you never run out of fresh drinking water while out there on the sea.

‍Energy efficient

Cost-effective

‍Comes with a very low speed

Not ideal for large boats

Spectra Katadyn PowerSurvivor

sailboat fresh water system

As a compact and energy-efficient watermaker, the Spectra Katadyn PowerSurvivor is arguably the most affordable watermaker currently available on the market. We are talking about a model that only requires 4 amps to desalinate water for your sailboat. It can produce 1.5 gallons of fresh drinking water per hour, which is an excellent return for a watermaker of its size.

It is also one of the most portable watermakers around. You can choose to either install it permanently or temporarily in case you want to take it somewhere else. This portability is also essential if you're looking for a space-saving model that can fit in the smallest of compartments. Its simple but rugged design is essential in ensuring that it can perform at its best even in harsh marine conditions. In terms of its power capabilities, this is the only model on the market that will convert to a hand-operated system or manual power if there's a power shortage.

‍Portable and lightweight

Rugged design to withstand harsh marine environments

Efficient and reliable

Can revert to manual power if there's a power shortage

Perfect for off-grid sailing

‍Gasoline or diesel can easily damage the semi-permeable membrane

Village Marine - Little Wonder Series

sailboat fresh water system

Whether you're looking for a watermaker for your small sailboat or looking for a watermaker that can efficiently serve those huge yachts, the Village Marine Little Wonder Series provides everything. This model is meant for experienced sailors who are looking for various capacity options. This watermaker weighs just about 69 pounds but can produce nearly 180 gallons of fresh drinking water each day.

Designed with a low RPM high-pressure pump, this model remains one of the most efficient and economical watermakers on the market. That's not all; this watermaker is designed with corrosion-resistant features and is one of the most serviceable watermakers in the game. It is reliable, quiet, and portable; all factors that make a watermaker great.

‍Easy to operate

Corrosion-resistant

Easy to maintain

Quiet and versatile

‍It doesn't have automatic adjustment controls

Ventura 150 Watermaker

sailboat fresh water system

This is one of the most versatile watermakers on the market. It can use both electricity and renewable energy. This model is engineered to be lightweight and energy-efficient and its compact and modular design makes it a great option if you're looking for a watermaker that's easy to use and install in confined spaces.

The Ventura 150 watermaker is highly efficient as it can produce over 6 gallons of water an hour, which makes it quite perfect for small vessels. This sailboat watermaker features a controller that allows you to operate and monitor the device remotely. It also has the auto store button that will automatically flash the system after every five days.

This watermaker is quiet and surprisingly compact despite its ability to produce about 150 gallons of water per day. It also gives you the option of going for the automated manual or manual model.

‍Very versatile

Can use both electricity and renewable energy power

It is smooth and quiet

It is compact and lightweight

‍The manual model has analog controls

To this end, it's easy to see that having an ideal watermaker aboard your vessel is one of the first crucial steps towards being self-sufficient and sustainable. With a watermaker, you'll be able to access fresh drinking water at all times when sailing even in far-flung places. Most of these models are well-constructed and incorporate some of the best technologies that make them efficient, reliable, and easy to install, use, and maintain.

So when it comes to choosing the best watermaker for your sailboat, it may all come down to what is ideal for you in terms of energy consumption, efficiency, the quantity of water produced, among many other things. With an ideal watermaker, you can remain off the grid for as long as you want without ever worrying about running out of water and this is of great importance in enjoying your sailing adventures.

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  • NEWS FEATURE
  • 04 July 2024

How do you make salty water drinkable? The hunt for fresh solutions to a briny problem

  • XiaoZhi Lim 0

XiaoZhi Lim is a freelance writer in Singapore.

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Two young girls collect rain water running off a roof and pour it into a container during monsoon rains in Bangladesh

High levels of sodium in drinking water have been linked to increased rates of pre-eclampsia in Bangladesh. Credit: Paula Bronstein/Getty

People have been separating salt from water for millennia, harvesting both salt and fresh drinking water from salty seawater. But there are limits to what can be done — sometimes with drastic consequences. When people in ancient Mesopotamia couldn’t work out how to desalinate their irrigation water and prevent salts from accumulating in their soils, their society collapsed. “It’s kind of the world’s oldest, most boring, but serious problem,” says Sujay Kaushal, a hydrologist at the University of Maryland in College Park.

This problem is now growing more pressing, as salinity levels creep up in fresh waters for a slew of reasons. Rising sea levels are pushing salt into coastal groundwaters, while excessive groundwater extraction in other places is drawing deeper, saltier waters up into aquifers. And human activities — from deicing roads to washing clothes and fertilizing fields — are polluting surface waters with many kinds of salt. Last October, Kaushal and his colleagues reported that salt levels in major streams and rivers around the world are booming; some bodies of water are now several times saltier than they were a few decades ago 1 . Freshwater salinization is a massive global problem, not just a regional one, he says.

A second, related issue is the growing burden of problematic waste brines. A variety of industries — from oil and gas extraction to the desalination plants that produce drinking water — create salty waste waters that are costly to dispose of. “We need to do something with the brine,” says Menachem Elimelech, an environmental engineer at Yale University in New Haven, Connecticut.

sailboat fresh water system

New desalination technique yields more drinkable water

On the flip side of these problems is the salt-mining industry. Hundreds of millions of tonnes of mineral salts are extracted every year from rock or briny waters. The Dead Sea is a major source of potassium; the Great Salt Lake in Utah, magnesium. Mining companies seeking supplies of lithium, a metal crucial for batteries and green technologies, are turning to brines around the world.

Researchers who sense opportunities in this field are hoping that they can extract salts from waste brines, turning a problem into a profit while squeezing out more fresh water.

To do all that, scientists are now exploring techniques to separate salt from water more efficiently, using electricity, new materials and solvents. With a wide range of brine chemistries to tackle and a host of different goals, there isn’t one “killer” technology, says Shihong Lin, an environmental engineer at Vanderbilt University in Nashville, Tennessee. “This is like a thousand different problems,” says Lin.

Super salty

It’s clear that extremely salty water isn’t healthy for humans, animals or plants. Drinking seawater, which contains about 3.5% salt, most of it sodium chloride, can shut down our kidneys and be fatal. Brackish groundwater, which contains around 0.1–1% salt, is typically desalinated before drinking. But the health impacts from less-salty water are murky. “Whether you can drink it for 30 years without any problem, not increasing any risk of disease, nobody knows,” says Lin.

There’s no agreed limit for a safe level of salt in drinking water. The World Health Organization suggests that drinking water should have sodium levels below 200 milligrams per litre (0.02%) and chloride levels below 250 mg/L (0.025%), but these guidelines are based mainly on taste. Kaushal points to a study that has linked drinking water with sodium levels of more than 0.03% to increased rates of pre-eclampsia and gestational hypertension among pregnant people in Bangladesh 2 . Salty water could also pose indirect harms, for instance by helping heavy metals to leach out of soils or plumbing as these metals swap places with salt in the water, says Allison Lassiter, a social scientist at the University of Pennsylvania in Philadelphia.

With salinity on the rise, specialists agree that the top priorities should be to stem salt-polluting human activities, conserve fresh water and reuse waste waters. But many researchers, including Lassiter and Kaushal, expect desalination to be increasingly needed as a buffer against freshwater scarcity.

Aerial bird's-eye view of an excavator digging lines containing bright yellow brine water in a white salt flat

Lithium mines in Chile spread brines over vast areas to evaporate the water. Researchers are seeking alternative, more compact methods of extracting lithium salts. Credit: Cristobal Olivares/Bloomberg/Getty

A standard method for desalination involves heating seawater to evaporate the water, then condensing the vapour; this basic principle is used today in a large number of the world’s desalination plants, especially those that dot the coasts of the Gulf in the Middle East. But this method consumes a lot of energy.

A more energy-efficient technique emerged in the 1960s, using physical pressure to force water molecules through tiny pores of a thin membrane while leaving dissolved salt ions behind. This process, called reverse osmosis, is the gold standard for desalination plants today.

The trouble is that reverse osmosis has a limit. As fresh water is extracted, the source waters get ever-saltier, making it harder and harder to continue the separation process. This is an “inescapable problem”, says Christopher Fellows, a chemist at the Saline Water Conversion Corporation (SWCC) in Jubail, Saudi Arabia. All forms of desalination leave a waste brine that needs to be managed.

Mine the brine

Some waste brines are simply put into the ocean; in California, a pipe system called the Brine Line carries waste brines that are produced more than 100 kilometres inland out to sea. In other places, the most economical solution is to inject waste brines underground, in a spot far enough away from utilized groundwater. This technique has been criticized for its potential to cause micro-earthquakes.

sailboat fresh water system

Sustainable implementation of innovative technologies for water purification

Alternatively, brine can be spread out in ponds to evaporate under the Sun, and the leftover salts collected — a land- and time-consuming strategy that also demands an amenable climate. A faster, more compact way to concentrate brine entails heating it and compressing the water vapour to accelerate evaporation. But this requires a staggering amount of energy, says environmental engineer Ngai Yin Yip at Columbia University in New York City, as well as expensive alloys that can withstand corrosive hot brine.

Paying for the safe disposal of brines can be exorbitant. Communities that have brackish groundwater, for example, sometimes can’t afford desalination because of the costs of brine disposal, and so must find fresh water elsewhere. Researchers who have suggested desalinating California’s Salton Sea — which is growing so salty that it threatens the wildlife living in it — are also contending with high brine-management costs.

Rather than throwing it away, some researchers are thinking about mining waste brines for minerals. For environmental engineer Jason Ren at Princeton University in New Jersey, this idea aligns better with his opinion that clean drinking water should be a human right: desalination companies, he says, should profit from selling salts, not clean water. “For many years, we’ve missed the point,” says Ren. “We focused on the water as the product; in my view, water should be a by-product of the other resources.”

Ren and others have their sights set on one particularly valuable mineral: lithium. Today, a large chunk of the world’s lithium supplies comes from natural brines in arid South America. The brine is spread out in sprawling ponds, evaporating under the Sun for many months. As researchers identify other lithium-rich brines — including waste waters from the oil and gas industry — they are realizing they need new techniques to suit places where there isn’t enough land or the right climate for evaporation ponds.

Close-up of white salts crystallising on blue twine

Researchers at Princeton University in New Jersey use the principle of chromatography to separate lithium from water and other salts along vertical strings. Credit: Bumper DeJesus/Princeton University

Other brines could provide an unconventional source of sodium chloride. Today, ironically, some companies use fresh water to mine salt: they puncture underground salt deposits with pipes carrying fresh water to dissolve sodium chloride. This highly pure brine is then pumped up and piped or transported to chlor-alkali plants — more than half of all chemicals produced rely on these chemical refineries.

Even if waste brines don’t contain any particularly valuable salts, water researchers have other reasons to champion the idea of mining waste brines: removing salt from brine liberates more fresh water, and the cost of disposal drops when volumes of waste brine are smaller.

Fresh solutions

In Saudi Arabia, recognizing the opportunity to bring in extra revenue while producing more fresh water, the government-owned SWCC is now building a demonstration plant to harvest sodium chloride, among other salts, from seawater desalination wastes.

The plant, scheduled to break ground at the end of this year in Haql, Saudi Arabia, uses an emerging salt-sorting technique called nanofiltration as part of a long string of processes, says Fellows. Like reverse osmosis, nanofiltration works by pushing water molecules across a membrane. But the membrane has larger pores that also allow some salt ions through: dissolved salt ions carrying only one electrical charge, such as sodium, potassium and chloride, can cross the barrier, whereas those with two or more charges, such as magnesium and calcium, stay behind. The SWCC’s key challenge is to produce sodium chloride that is pure enough for the chlor-alkali market.

The final stage at the SWCC plant entails boiling the hot brine until pure sodium chloride crystallizes. This energy-intensive step is far from ideal, says Fellows. His team has begun exploring other strategies for this stage, including freezing desalination. This approach is inspired by the fact that sea ice is composed of fresh water, even though seawater is salty. It is alluring, Fellows says, because it takes one-seventh of the energy to freeze ice-cold water as it does to evaporate boiling water. “I don’t know what’s the winning [strategy] at the moment, but it will be different for the different separations we want to do,” says Fellows.

Many groups are focusing on an alternative strategy that uses electricity, rather than pressure, to do the work of separation. In this technique, an electric current is used to pull dissolved salt ions across specialized ion-exchange membranes, which permit the movement of ions in one direction only. As the ions pass through these membranes, the brine they started out in becomes more dilute, or fresher. Researchers expect the technique to be useful for pre-diluting extremely salty brines so that conventional reverse osmosis can then be used to squeeze out more fresh water.

In one variant of these electricity-based techniques, Lin’s team tried to let the concentrations of salt ions that have crossed the ion-exchange membranes build until they form solid crystals 3 . This attempt to crystallize salts without evaporating the water worked well for certain salts — such as sodium sulfate, which is commonly found in power-plant waste water, Lin says — but not for the most abundant salt in waste brines, sodium chloride. Sodium and chloride ions hold on to water molecules so tightly that they also drag the water across the membrane, Lin says.

To avoid both evaporation and the use of membranes, Yip’s team members at Columbia are instead looking to chemical solvents 4 (see video). One promising candidate is an off-the-shelf solvent called diisopropylamine 5 . The solvent floats on top of a salty brine and — at low temperatures — selectively sucks water molecules into itself, leaving most of the salt ions behind. At higher temperatures, diisopropylamine switches to repelling water and spontaneously expels the water that it has absorbed, so the water can be recovered and the solvent reused.

Yip says his team has used this method to recover fresh water from brine samples that are up to ten times as salty as seawater — an impossible task for standard reverse osmosis. The fresh water portion might not be potable until further steps are taken to remove contaminant solvent and salt, the researchers say. But the technique could aid industries that are seeking to recycle water from their waste brines. The researchers are currently participating in a prize challenge organized by the US Department of Energy to build a small pilot that would use solar heat for the water-expelling step.

Ren and his colleagues have taken an entirely different approach 6 , inspired by trees. Trees can draw water up several metres against gravity, emitting clean water vapour from their leaves while trapping dissolved compounds in their tissues. His team's approach mimics trees by using long strings of fibres with one end soaking up salt water. As the brine travels upwards, the salts are separated leveraging the common principle of chromatography — different compounds move at different speeds through a medium.

Ren’s main target, lithium chloride, is extremely soluble and small, so its ions move quickly up the string, ahead of larger sodium ions. Ren has successfully used this method to recover lithium from natural brine samples from Chile, using less energy and space than conventional evaporation. The team is designing an enclosed module incorporating stacks of these strings. The researchers aim to extract lithium from waste brines produced from oil and gas operations, while recovering the evaporated water.

Yet more inspiration could be found in nature: highly-selective channel proteins embedded in cell membranes. One type of ion channel allows just one sodium ion to pass through for every thousand potassium ions, says Elimelech. His team is currently working on membranes that mimic these channel proteins, although for now they are in the earliest stages of development.

Price barrier

Whether any of these ideas will take hold depends on economics. If the SWCC mined all the available sodium chloride from Saudi Arabia's seawater desalination brines, Fellows notes, it would be enough to supply one-third of the world’s market. Meanwhile, waste brines left over from brackish-water desalination could offer the plentiful mineral gypsum, but it’s unlikely that unconventional brine mining could compete economically with conventional quarrying from rock.

New markets, such as the advent of salt-fuelled technologies including zinc–bromine batteries, could create fresh demand for certain salts, says Fellows. Regulations could also play a part, either by making it more expensive to dispose of waste brines or by incentivizing the use of brine-sourced salts in various applications, for instance brine-sourced gypsum in road salts.

One thing is clear: freshwater needs are increasing. Addressing the current limits of desalination with new technologies is important, researchers say. But it isn’t an alternative to the still-essential step of conserving fresh water. It will always take energy, time or land space to separate salt from water, so there will always be a price to pay for desalination. “There’s no magic there,” says Elimelech.

doi: https://doi.org/10.1038/d41586-024-02073-6

Kaushal, S. S. et al. Nature Rev. Earth Environ. 4 , 770–784 (2023).

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Khan A. E. et al. PLoS ONE 9 , e108715 (2014).

Zhang, X. et al. Nature Water 1 , 547–554 (2023).

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Boo, C., Winton, R. K., Conway, K. M. & Yip, N. Y. Environ. Sci. Technol. Lett. 6 , 359–364 (2019).

Boo, C., Billinge, I. H., Chen, X., Shah, K. M. & Yip, N. Y. Environ. Sci. Technol. 54 , 9124–9131 (2020).

Chen, X. et al. Nature Water 1 , 808–817 (2023).

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IMAGES

  1. Get your Freshwater System Ready for a Season Afloat

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  2. Installing a New Freshwater System on our Sailboat

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  1. Fresh Water System and Filling

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COMMENTS

  1. Pressurized Freshwater Systems Guide

    Pressurized water systems make life aboard more comfortable by providing water "on tap" for dishwashing, showers and other applications. The complexity of installing and maintaining one depends on the number of outlets and accessories you choose. The Whale Water System is a user-friendly system for the do-it-yourself boat owner.

  2. Get your Freshwater System Ready for a Season Afloat

    Flushing the system. Commissioning your boat's freshwater system consists primarily of making sure it is purged of any antifreeze that was introduced when it was decommissioned. Start with the water tank. Open the inspection port and pump or sponge away any puddles of antifreeze that may be present below the freshwater pickup.

  3. 5 Best Watermakers for Sailboats

    Spectra Katadyn PowerSurvivor. As a compact and energy-efficient watermaker, the Spectra Katadyn PowerSurvivor is arguably the most affordable watermaker currently available on the market. We are talking about a model that only requires 4 amps to desalinate water for your sailboat.

  4. Keeping Water Clean and Fresh

    For treating water that is clear and chlorinated at the tap, 1 teaspoon of bleach per 50 gallons will provide a 2 ppm booster, the very most that should be needed. Chlorine aftertaste is the most common onboard water-quality complaint; however, chlorine at the tank can be efficiently removed with carbon filtration.

  5. Installing a New Freshwater System on our Sailboat

    In this episode, Zach works on the plumbing in the Island Packet 31. Running water is going to be a game changer. Thanks for watching! Product Links: Quick C...

  6. Upgrading the Water Systems

    However, with the nylon hose tees you'll also need six stainless steel hose clips at a cost of $1.99 each, bumping the total price tag for the "low-cost" solution up to $33.21. West Marine lists Whale's 15mm tubing at $1.49 per foot (blue), compared to food-grade reinforced 5/8in PVC hose at $1.79 per foot.

  7. Watermaker for Sailboat, Desalination for Sailboat

    Since all of the watermakers that are currently available for cruising sailboats use this process for desalination, the major differences between the systems are how you power the high-pressure pump and the user interface. Powering options include 120/220-volt AC, 12- or 24-volt DC and engine/belt driven. All have their pros and cons.

  8. Smelly "fresh" water

    Turn on every faucet on the boat (including a deck wash if you have one), and allow the water to run until what's coming out smells strongly of bleach. Turn off the faucets, but leave the system pressurized so the solution remains in the lines. Let stand overnight--at least 8 hours--but NO LONGER THAN 24 hours.

  9. 7 Best Sailboat Watermakers For Liveaboards 2024

    The best sailboat watermakers for liveaboards. The Rainman naked 12V watermaker is a great option for anyone looking for a compact, efficient way to produce fresh water. The unit is simple to set up and use, and it produces up to 30 litres of fresh water per hour for a smaller unit, or up to 140 litres per hour for a larger one.

  10. Finding leak in fresh water system

    I've started noticing a small amount of water (3-4 gal) in the bilge, and I've narrowed things down to a leak in my fresh water system. I've included a drawing of my water system. My first troubleshooting step was to fill the tanks, shut all the intake manifold valves, and then shut down the water pump.Then let the boat sit for a few days. Good news there wasn't all water in the bilge, and ...

  11. Best Boat Watermakers for Your Yacht

    The newly made freshwater is then pumped into your vessel's current water tank, while the leftover "brine" is thrown overboard. Most marine watermakers differ with regards to the method in which the water is pumped. Typically, the water can be either electrically driven (either AC or DC) or powered by your boat's engine.

  12. Troubleshooting Your Boat's Fresh Water System

    Whale photo. Remove the fresh water supply hose from the hand pump to see if water is flowing from it. If water flow is not present you can try moving the hose end to a lower point in the boat or simply try sucking on it like a straw. If there's good water flow, then your hand pump likely needs a rebuild.

  13. How Do Sailboats Get Fresh Water? (4 EFFECTIVE SOLUTIONS)

    One of the most effective solutions for sailboats to get fresh water is by collecting rainwater. Sailors can use a variety of methods to collect rainwater and store it on board. These include using a tarp to collect rainwater, using a rainwater catchment system to collect and store large amounts of water, or using a container to collect smaller ...

  14. Fresh-Water System Problem

    Nov 10, 2004. 64. - - Falmouth, ME. Jan 16, 2008. #2. I am having a problem with the fresh water system on our 1989 Catalina 30. The problem is two fold. The first part is the water pump (Shurflo) will not reach the level of pressure required to turn it off. The second issues is when the pump is on and a faucet in the boat is opened, water ...

  15. The Care And Feeding Of Your Boat's Water Systems

    Seawater Washing (1) — Seawater systems such as anchor washdown and dishwashing with a seawater foot pump (if you're in clean water and rinse well with potable water) can conserve water. Frequently bathing in saltwater causes skin problems in many people; a freshwater rinse helps. Washdown water pump should be a short distance from the thru-hull but above the waterline.

  16. Fresh Water System

    Looking for advice on my fresh water system. My 1991 Hunter 28 is a great boat that I sail a lot but never use the water system. I filled it a year ago just to test it out, and while the pump worked fine, I couldn't get any hot water. ... Looking for advice on my fresh water system. My 1991 Hunter 28 is a great boat that I sail a lot but never ...

  17. How To Clean Your Boat's Freshwater Tank (Plastic & Aluminum)

    Drain the tank completely. Measure 1 teaspoon/gallon of household bleach (aluminum) or vinegar (plastic) into the tank and add fresh water until it's full. Let it sit for 24 hours to sterilize, then drain the water. Fill with fresh water and drain repeatedly until all the bleach/vinegar odor is gone.

  18. Buy portable water maker. Turn saltwater into fresh water in 10 minutes

    Put the intake hose into seawater. Put the green waste brine hose overboard. Turn the system on. Slowly pressurise the system to 55 bar (800 psi) using the control valve. Fresh water will begin coming out of the white product water hose. Let it run for a short period of time, then put it in your tank.

  19. Fresh Water Boat System Pumps & Accessories

    Fresh Water Boat Systems is primarily for boats that have the capacity to store and move fresh water, usually for at a sink or shower in the cabin. In addition to the water pressure pumps required for a fresh water system, we offer things like water tanks and heaters, sinks, showers, pressure regulators, and chemical treatments. ...

  20. Freshwater Systems

    Ensure your boat has the best possible freshwater system by purchasing quality parts with the correct capacity and power for your needs. Reliable Water Flow. To ensure your boat has reliable water flow to all faucets and showers, you must have a freshwater system designed to accommodate the size and use patterns of your boat.

  21. Choosing and Installing a Washdown System

    Install your pump in an out-of-the-way but accessible location. Locate the pump above the high-water mark of the bilge, although most of these pumps are designed for use in wet locations. Washdown pumps are often installed in a protected location under a boat's gunwale or in a cockpit locker. Our 4.0GPM Washdown Pump Kit is great for general ...

  22. Watermakers

    Welcome to SeaWater Pro, the premier provider of high-quality watermakers for boats and portable watermakers for all your marine adventures. Our cutting-edge technology and reliable products will ensure that you have access to clean, purified seawater wherever you go. With our easy-to-use and reliable watermakers, you can say goodbye to bulky storage tanks or worry about running out of fresh ...

  23. 5 Best Watermakers for Sailboats

    Last Updated by Daniel Wade, October 1, 2021With the right Watermaker, the ocean becomes an almost immeasurable supply of fresh and clean drinking water to keep you hydrated during your offshore sailing adventures.Many sailors do spend a lot of their time and money on various parts of the sailboat including the sails, engine, electronics, and generators especially when preparing for long ...

  24. How do you make salty water drinkable? The hunt for fresh ...

    As fresh water is extracted, the source waters get ever-saltier, making it harder and harder to continue the separation process. ... The Solar System has a new ocean — it's buried in a small ...