Tips for Choosing The Best Watermaker For You!


Embarking on long journeys at sea necessitates meticulous planning, and one of the foremost considerations for every boater is securing a dependable source of freshwater. Whether exploring uncharted waters or cruising along well-traveled routes, having access to clean and safe drinking water is paramount. This is where watermakers come into play. Watermakers are sophisticated onboard systems designed to convert seawater into potable water, ensuring a continuous and sustainable supply for your essential needs. In this comprehensive blog post, we will not only compare and contrast three popular watermakers – the Katadyn Powersurvivor 40E, the Zen 30, and the SeaWater Pro – but also delve into the preconditions, benefits and critical considerations involved in selecting the ideal watermaker for your boat.

The Benefits of Having a Watermaker Onboard

Having a watermaker onboard your boat is nothing short of a game-changer. It’s often considered one of the most critical equipment for sailors and boaters, and for good reason. And if you plan to live aboard your boat for extended periods, it’s almost mandatory. Let’s delve into the compelling advantages that make a watermaker indispensable:

Independence and Self-Sufficiency: A watermaker allows you to generate your freshwater supply while at sea. You no longer depend on finding freshwater sources or carrying large water reserves, giving you more autonomy to explore remote or less populated areas.

Endless Supply of Freshwater: With a watermaker, you can produce freshwater continuously, ensuring a consistent and ample supply for drinking, cooking, cleaning, and even showering. This convenience enhances your comfort and reduces the need to ration water during long journeys.

Cost-Efficiency: Over time, a watermaker can lead to significant cost savings. Instead of purchasing bottled water or relying on shore water supplies, you can produce your freshwater at a fraction of the cost, making boating more economical in the long run.

Reduced Environmental Impact: Using a watermaker reduces your reliance on single-use plastic water bottles, which are harmful to the environment. Producing fresh water onboard minimizes waste and helps reduce your carbon footprint while sailing.

Health and Safety: Having a dependable source of freshwater onboard is convenient and crucial for your health and safety. You can ensure your water is clean and free from contaminants, reducing the risk of waterborne illnesses.

Extended Cruising Range: Watermakers enable you to extend your cruising range and explore more distant destinations without worrying about freshwater availability. This opens up a world of opportunities for adventurous sailors.

Emergency Preparedness: Watermakers provide an essential backup plan in case of emergencies or unexpected delays at sea. Having the ability to produce freshwater can be a lifesaver in critical situations.

Increased Resale Value: Boats equipped with watermakers tend to have higher resale values. Potential buyers recognize the value of having this essential piece of equipment already installed, making your boat more attractive on the market.

Factors to Consider When Choosing a Watermaker

Several key factors should be considered when selecting the right watermaker for your boat. Here are some essential considerations to keep in mind:

  • Water Production Capacity:
    • Evaluate the water production capacity of the watermaker. This should align with your daily freshwater needs, which depend on the size of your crew and the duration of your voyages. Smaller boats with fewer occupants may require less capacity, while larger vessels or long-distance cruisers need a higher output.
  • Power Source:
    • Determine the power source available on your boat. Some watermakers are designed to run on DC power from your boat’s batteries, while others require an AC generator or shore power. Ensure the chosen watermaker can easily integrate into your vessel’s electrical system.
  • Installation Space and Weight:
    • Consider the available space and weight limitations on your boat. Smaller boats may have limited installation space, making choosing a compact and lightweight unit essential. Larger vessels can accommodate bulkier systems but may have different weight restrictions.
  • Maintenance Requirements:
    • Assess your willingness and ability to perform regular maintenance on the watermaker. Some units require frequent upkeep, such as filter replacements and system cleaning, while others are designed for minimal maintenance.
  • Budget Constraints:
    • Determine your budget for a watermaker. The initial cost varies significantly between models, and you should consider the purchase price, ongoing operational costs, and maintenance expenses.
  • Water Quality and Salinity Levels:
    • Understand the quality of seawater in the areas you plan to navigate. Some regions may have higher salinity levels or increased impurities, affecting your watermaker’s performance and maintenance needs.
  • Automation vs. Manual Operation:
    • Decide whether you prefer an automated system that requires minimal user intervention or a manual one that gives you more control but demands more effort. The choice depends on your comfort level with the equipment and your willingness to monitor its operation.
  • Reliability and Durability:
    • Look for a watermaker from a reputable manufacturer known for producing reliable and durable marine equipment. Read reviews and seek recommendations from other boaters to gauge the reliability of a particular model.

One final aspect to consider is how often and for how long you need to run your watermaker. Even if you have a large water tank, there might be better options to fill up your tank, let’s say every 10 days. A watermaker will last longer and work better if used regularly. On average, you should run your watermaker every 3rd day to avoid bacteria growth. If you don’t use your system for an extended period, you must pickle the system to preserve it.

Matching Your Needs with the Right Watermaker

Once you have considered the above factors, you can match your specific needs with the watermaker that best suits your boat. Here’s a general guideline to help you choose:

  • For Small Boats and Minimal Crew: Consider compact and energy-efficient models like the Katadyn Powersurvivor 40E, which offers adequate freshwater production without overwhelming your boat’s space or power resources.
  • For Mid-Size Boats with Moderate Water Needs: The Zen 30 may be a suitable choice, offering a balance between capacity and efficiency for boats with a moderate crew size and average freshwater requirements.
  • For Large Vessels or High Water Demands: If you have a larger crew or need a high volume of freshwater, the SeaWater Pro’s exceptional production capacity and durability make it a strong contender, even though it comes at a higher initial cost.

Remember, there is no one-size-fits-all solution when it comes to watermakers. Carefully assess your boat’s unique circumstances and requirements to make an informed decision that ensures a consistent and reliable supply of fresh water during your voyages.

My short list of watermakers

  1. Katadyn Powersurvivor 40E:
Katadyn PowerSurvivor 40E watermaker

If you are looking for a small and reasonably affordable watermaker, it’s hard not to have a look at the PowerSurvivor 40E. When I started looking for a watermaker, this quickly became a favorite, first of all, due to the price, but also the size and the low power consumption. I’ve found some reviews online that have highlighted potential quality issues with this unit, and I urge anyone who considers this unit to ask existing users for their input before buying it.


  • Its compact and lightweight design makes it suitable for smaller boats.
  • Energy-efficient operation with low power consumption 32Watts / 1 gal
  • Simple and user-friendly operation with a manual pump option.
  • Effective at removing salt and impurities from seawater.


  • More than limited production capacity (1.5 gallons per hour) may be required for larger crews.
  • Requires regular maintenance and replacement parts.
  1. Zen 30:
Schenker Zen 30 watermaker

The Zen 30 quickly became my favorite; it’s quiet, does not consume too much power, and has a good throughput. On top of that, it’s a well-established brand with good worldwide support. And if I had no budget restraint, I would not have looked any further since it checked all the boxes for me.


  • High production capacity, capable of producing up to 7.9 gallons per hour.
  • Energy-efficient with advanced energy recovery technology. (110 Watts)
  • Robust construction and durable components for long-term use.
  • Low noise and vibration during operation.


  • It is bulkier and heavier than other models, which may be challenging to install on smaller vessels.
  • More complex setup and maintenance compared to simpler units.
  • Higher initial investment cost.
  1. SeaWater Pro:
Sea Water Pro 20 GPH, Single Membrane watermaker

At some point, I started investigating the route of simply building a watermaker myself with off-the-shelf parts. I quickly realized this is the cheapest way for anyone wanting to make their own watermaker. Most of the parts needed are actually available on Amazon.

But during that process, I stumbled over Seawater Pro, which supplies all the necessary parts for building your system. But they also sell ready-made systems if you would prefer that.


  • Exceptional production capacity up to 20 gallons of fresh water per hour. Up to 40 on some models
  • Fully automated operation with minimal user intervention required.
  • Suitable for larger crews or vessels with high water demands.
  • Designed for durability and reliability in marine environments.
  • Modular and customizable for your needs.


  • Consumes more power compared to competition.


Choosing the best watermaker for your boat is crucial to ensure a reliable source of fresh water during your adventures at sea. Each of the reviewed models has its own set of advantages and disadvantages. Consider your boat size, crew size, availability of power, and budget. The Katadyn Powersurvivor 40E is a suitable choice for compact boats; the Zen 30 offers a balance of capacity and efficiency, while the SeaWater Pro caters to larger vessels with high water demands. Ultimately, the right watermaker will depend on your specific needs and preferences.

Remember to conduct thorough research, seek advice from fellow boaters, and consult with experts before making your final choice. A well-selected watermaker will ensure a constant and reliable fresh water supply, enhancing your boating experience.

As for me, I am still deciding what route to take. I would like to go with the Zen 30, but it’s way outside my budget. Instead, I’m leaning towards the SeaWater Pro solution or buying parts and building my custom system. You just have to wait for the next post to see my final decision. 

Now, everyone can afford the cost of a watermaker but don’t worry. Low-cost alternatives, like the manual and portable QuenchSea, are available on the market. It might be a short-term solution, but it will work as a backup or emergency solution. You can check out my post here if you are interested.

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