Desalination Units

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Why would I want a reverse osmosis desalination watermaker?

Peace of mind, fresh and safe drinking water. Unlimited supply of fresh drinking water around the world. With a Spectra, run your watermaker on renewable energy. On a yacht, keep stainless from pitting and corroding with fresh water washdowns. At Spectra Watermakers, we create products that make life simple and easy, and we believe in saving you time and power. With the push of a button you can have fresh water for drinking, cooking, showering, laundry, and if you’re on a yacht, fresh water wash...

Why shouldn’t I use my watermaker in a harbor?

Silt can damage the pumps and membranes. Harbors and inland waterways tend to have much siltier, cloudier water than offshore. That cloudiness is the result of suspended solids, stirred up from the ocean floor, runoff from nearby homes, nitrates from fertilizers, algae blooms, and other large particulates that can plug up filters and work their way into your system. The large particles can damage feed pumps, score the pistons and cylinders of the high pressure pumps, damage valves, or even foul ...

Why is my watermaker making less water than it’s supposed to?

As your system ages it is natural that certain parts wear over time. The issue of low product water quality is typically an issue with a worn feed pump head, or that it is time to rebuild the Clark Pump. Low production is not typically a problem with the membranes on Spectra Watermakers. We recommend that you keep a log so that you can see that the feed pressure has dropped, or the salinity has increased. There are technical bulletins in the manual that will help you understand what is happening...

Why can’t I wash my filters?

Washing the prefilters opens up the pores on the surface of the filter. These pores are specifically sized to capture particles as small as 5 microns. When the pores are opened up through washing, this allows larger particles through the filters, and can damage the pumps, valves, and membranes.

Where on a boat can I install a Spectra Watermaker?

This is really only limited by your imagination. We have seen system installed in lockers, under the cabin sole, in the top or bottom of a locker, just about anywhere.

Where do I buy parts?

Most major cruising ports around the world, with over 100 dealers worldwide. Spectra has over 100 distribution and technical representatives in 55 countries around the world so you’ll never be left stranded. Many representatives have attended our factory training and stock parts in their shops or can have parts drop shipped to you.

What spare parts do I need for a Spectra watermaker?

We have many spare part kits available for each system. We always recommend spare filters, and we also typically recommend carrying a spare feed pump head, and a seal & o-ring kit.

What size watermaker do I need?

The simple answer is “bigger than you think”. General recommendation: 5-20 gallons per day per person. In reality, it depends on how many people are going to be on the boat, where you plan to go and for how long, and what the weather’s going to be like. Most of our customers find that the ease of use, the quietness, and the convenience of our systems gives them the security to drink more water, take more showers, wash their decks down with fresh water instead of salt; all in all, they consume a ...

What is reverse osmosis?

The process of removing dissolved ions, like salt, from brackish or seawater. Reverse Osmosis is a filtration process that will separate individual water molecules from an undrinkable feed water source like seawater. In the case of seawater desalination, high pressure is required (800+psi) to force individual water molecules through the Reverse Osmosis (RO) membrane while flushing salts, minerals, viruses, bacteria or any other contaminant down the drain. Using seawater or contaminated brackish ...

What is energy recovery?

Our unique pressure amplifiers capture the high pressure from the brine waste stream that would normally be vented to atmosphere to help pressurize the seawater entering the system. The Clark Pump and Pearson pump are two of Spectra’s unique technologies. The Clark Pump is a pressure amplifier with built in energy recovery and the Pearson Pump is a piston pump with built in energy recovery. The beauty of these technologies is in the simplicity of their design; by recycling the high pressure brin...

What chemicals can I use to decommission or pickle a watermaker?

Due to the engineering plastics used in Spectra’s watermakers, we strongly recommend that you only use Spectra storage chemicals (SC-1) or a good quality brand of Propylene Glycol with no Ethyl Alcohol added. Using storage solutions from competing manufacturers, such as Sodium Metabisulfite, will permanently damage the membrane end plugs and the Clark Pump. Never use any chemicals with the system pressurized. Always open the pressure relief valve 1/2 turn. Always follow the instructions for purg...

What are the installation requirements?

A dry, well-ventilated area below 113 deg F. Easy access to pumps and controls and a dedicated thru hull. The system should be installed in a dry location with good ventilation and easy access to change the cartridge filters. Access to the pumps and MPC 5000 control system (if applicable) should be considered prior to installation. The intake thru hull must be installed in a location that will not be exposed to the air in heavy weather, behind stabilizer fins, or directly behind the keel. Never ...

Is reverse osmosis water safe to drink?

Yes, desalinated water is absolutely safe to drink. Reverse osmosis desalination is a process that uses a membrane to purify seawater or contaminated and undrinkable water sources by removing the dissolved salts and harmful content. The seawater membranes used in desalination systems remove salt, bacteria, viruses, protozoa, and cysts from the raw water, producing fresh, potable water. The seawater membranes used in Spectra’s watermakers remove 99.5% of all of the total dissolved solids from the...

How often do I fresh water flush a Spectra Watermaker?

Spectra recommends flushing your watermaker after every use. Why? Seawater contains two things that can shorten the life of any RO membrane; minerals and living organisms. If seawater is allowed to remain in contact with the membrane, minerals will begin to adhere to the surface; a fresh water flush will actually dissolve many minerals and stops this from happening. Seawater is also full of microscopic life and as the oxygen is consumed when the system stops, these organisms begin to die and dec...

How often do I change membranes?

Proper maintenance will ensure your membrane lasts 5-10 years. The life a membrane is directly dependent on how well it is cared for, which is why our many of our systems include automatic fresh water flushing. Keeping the membrane clean and stored in fresh water during voyages can add years to the service life of any membrane. Proper long term storage, or pickling, is also important for longevity. A well maintained reverse osmosis membrane can easily last 5 to 6 years, we have some customers wi...

How often do I change filters?

This depends on where you are making water. We recommend making water in the ocean where the water is fresher and cleaner as filters can last for months in these conditions. If you’re making water where there is algae, silt, plankton or other particulates, your filters may need to be changed more often.

How is Spectra different from other watermaker brands?

Hydraulically driven pump is quiet and extremely energy-efficient. Run on solar power, wind power, inverter, or batteries; no generator necessary. 20 years in the desalination industry and 30 in marine service with support you can count on. Spectra has spent years developing our patented high pressure intensifier pump technology with integrated energy recovery that allows us to create the high pressure required for RO based desalination, using a low pressure pump that will operate off your boat’...

How does a watermaker work?

In a conventional watermaker, a high pressure pump similar to a pressure washer, boosts the incoming raw water pressure up to 800-1000 PSI (55 - 69 Bar). Large pumps use brute force to hammer seawater against a back-pressure valve in order to generate this pressure. Only a small percentage of the water pumped through a watermaker passes through the membranes and comes out as fresh drinking water. The result is that a significant amount of energy is wasted pumping the entire quantity of raw water...

How do I winterize a watermaker?

These instructions are intended to be generic, and specific directions for your system are provided in the Operation and Maintenance Manual. Refer to your manual for specific system instructions and chemical ratios. For Analog Systems: 1. Close the thru hull. Fresh water flush the watermaker. Turn off the feed pump. Close the grey flush valve (located on feed pump module). 2. Connect the inlet service hose to the service intake on the feed pump module, and lead it into a bucket. Connect the ...

How do I take care of the feed pump?

Make sure your feed pump is properly installed, check regularly for vacuum leaks, do not allow air to enter your thru hull, and fresh water flush your system after every use. The feed pump is the workhorse behind your watermaker, and taking care of it will ensure a long lasting watermaker with few replacements and lots of good quality fresh water in your tanks. Most pump problems come from improper installations. Make sure the feed pump is mounted as low as possible in your boat and as near to ...

How do I commission a watermaker?

Refer to your manual for specific instructions. If this is the first time you have started your system, we recommend that you contact your local dealer to help you commission the system and walk you through the proper operation, care and maintenance of your new system. These instructions are intended to be generic, and specific directions for your system are provided in the Operation and Maintenance Manual. Refer to your manual for specific system instructions and chemical ratios. First, for...

Does Spectra make watermakers in AC voltages?

Yes, we do! Our AC watermakers are specifically engineered to reduce starting loads on your generators eliminating the need to stagger the loads on your generator during system startup. Our motor speed control systems are programmed so that if you don’t want to operate your generator, you can still fill your tanks with water while sitting quietly at anchor. In most cases our AC watermakers have a significantly smaller footprint than their conventional counterparts, which means you will have even...

Do I need an oil/water separator?

If you need to make water in a harbor or shallow water where there may be oil, having an oil/water separator will be beneficial. If oil is in the feed water and is not removed, the membranes can be permanently damaged. Best practices are to not operate the system in waters where you can see an oily sheen on the water.

Do I need a UV Sterilizer?

Reverse osmosis will remove salt, bacteria, viruses, protozoa, and cysts from the raw water, however, adding a UV Sterilizer is a good precautionary measure and an added level of protection. Many customers choose to install the UV sterilizers at the point of use, near a faucet or drinking water tap, as opposed to the output of the watermaker, since this protects from anything that may have contaminated the fresh water tanks.

Do I need a generator to have a watermaker?

Not at all! Most of our watermakers are designed to run on 12 or 24v, without a generator running. Our watermakers are designed to run on 12 or 24v DC batteries without a generator running, or even off an appropriately sized inverter and battery bank. We build a full line of DC watermakers ranging from 1.5 to 120 gallons per hour (24.6 to 1590 liters per hour) of fresh, potable water. Our inverter-ready AC line of watermaker can all operate whisper quiet without a generator as well. All equipme...

Can I use it in warm water?

Yes! Spectra Watermakers will work in warm water. Spectra Watermaker will work extremely well in warm water. The power consumption may even be lower than normal. All of our systems are designed to be inherently self-balancing, so at the water temperature rises, there is no need to make any adjustments to your watermaker at all. Just start the system up and enjoy the water at its full rated capacity.

Can I use it in cold water?

Yes! Spectra Watermakers will work in cold water. Spectra Watermakers are rated to work in near freezing water. The one exception is the Ventura 200T which is rated at 50 degrees Fahrenheit. Many customers have used our watermakers in arctic waters with much satisfaction. You can read about S/V Kotik in Antarctica on our blog here: S/V Kotik in Antarctica (https://www.spectrawatermakers.com/us/us/news/13735). All of our systems are designed to be inherently self-balancing, so at the water tempe...

Can I run a Spectra Watermaker on solar panels or a wind generator?

Yes, Spectra Watermakers were built to run on solar and wind power! Our watermakers are designed to run on 12 or 24vdc batteries, without a generator running. We build a full line of DC watermakers ranging from 1.5 to 120 gallons per hour (24.6 to 1590 liters per hour) of fresh, potable water. All equipment is designed to avoid high start-up loads with soft start technology, energy recovery to reduce the operating power required, and automated controls to make operation as efficient and as simp...

Can I run a Spectra Watermaker on an inverter?

Our AC powered systems are built using a soft-start motor speed controller so the starting loads are very low; this means that most inverters are more than capable of starting and operating your AC watermaker without ever turning on the generator. The starting load will not exceed the normal running load.

Can I make water underway?

Yes, as long as you have a forward facing thru hull and there is no air entering the thru hull. In most cases you can make water while underway as long as you have a forward facing scoop on your thru hull. The forward facing scoop will take your boat’s forward motion and “push” water up through the watermaker intake and into the system, allowing you to fill your tanks as you cruise along. Planing boats, high speed racing monohulls and multihulls should all use caution when operating their syste...

Are watermakers noisy?

Spectra Watermakers are absolutely the quietest watermakers available. Despite the marketing hype from our competitors to the contrary, conventional watermakers are intrusively noisy. Have you ever heard a pressure washer drone on? Spectra Watermaker’s systems are truly quiet because the Clark Pump is hydraulically driven, it has slow moving, quiet parts that cause very minimal vibration. Compare the cycle rate of Spectra’s Clark Pump at 4 - 8 cycles per minute, compared to the high pressure pu...

How long do Spectra Watermakers last?

Flush your system with freshwater after every use. We have customers still using the first units we built back in 1998 because they flush their systems properly. Spectra Watermakers are constructed of modern composites and engineered plastics to deliver many years of quiet, reliable service. Since the Clark Pump is hydraulically driven, it has slow moving parts that do not wear easily. You can ensure your watermaker lasts many years by regularly changing your prefilters and flushing it as recomm...