A watermaker for a cruising yacht is not a luxury once you leave the marina behind. It is the difference between rationing every litre and cooking, washing and drinking freely at anchor. The right unit depends on your daily water budget, your crew size, your power setup and how far offshore you plan to go. This guide walks through each of those factors and shows you which system makes sense for your situation.
How Much Water Does a Cruising Yacht Actually Need?
The baseline most cruisers work from is 3 to 5 litres per person per day for drinking and cooking. Add showers, rinsing fruit, topping up a pet's bowl and the real number climbs to 10 to 20 litres per person per day. A couple on a 38-foot sloop for a week-long passage needs somewhere between 140 and 280 litres. A family of four on a catamaran for a Pacific crossing needs considerably more.
Those numbers tell you what output rate you need. If you can run your watermaker for a couple of hours each morning, you need roughly 10 to 20 litres per hour (LPH) for a couple, and 40 to 80 LPH for a larger crew or charter operation. Getting this number right first means you will not buy too little or pay for more than you need.
For a deeper look at real daily water consumption, see How Much Water Do You Actually Need?
Portable vs Installed: Which Suits a Cruising Yacht?
Most cruising yachts fall into one of two camps. Smaller boats, 20 to 50 feet, with limited locker space or owners who move between vessels, tend to do better with a portable unit. Larger liveaboards, charter yachts and serious blue-water passage makers often want a system plumbed in below decks.
A portable watermaker sits in a cockpit locker or below decks, comes out when you need it, drops its intake hose over the side and makes water. No plumber, no installation cost, no hull penetrations. A below-deck system is always ready at a switch press but requires installation, takes up a permanent locker, and is harder to service in a remote anchorage.
The honest trade-off with portable is that it runs manually rather than at a button. That suits most cruisers who are already on deck each morning anyway.
See also: Portable vs Installed Watermaker
The LEDI Scout: Best Fit for Smaller Cruisers
The LEDI Scout is built for trailer sailers, cruising yachts from 20 to 50 feet and catamarans where you want water independence without a refit. It produces 10 or 20 LPH, weighs 18 kg, and one person can carry and deploy it in minutes. There is no installation required: drop the stainless intake over the side, connect the supplied hoses, switch it on.
- Output: 10 LPH or 20 LPH
- Power: 12V DC, 16 to 18A draw, runs comfortably off a 12V house bank with 200 to 400W of solar, no generator needed
- Weight: 18 kg, single-person carry
- Salt rejection: 99.4%, output typically 250 to 300 ppm TDS (well under 800 ppm)
- Built-in UV steriliser, meets Australian drinking-water standards
- Handles seawater to 35,000 ppm and brackish or river water
- High-pressure pump: Pumptec 107SS (USA-made, 316 stainless, around 800 PSI)
- Pricing: see current pricing on the Scout page
Because it is made on the Gold Coast and uses non-proprietary commercial marine-grade parts, servicing is straightforward anywhere in the world. Wear parts are field-replaceable. You are not locked into a proprietary service network in a remote Pacific anchorage.
The LEDI Nomad: For Bigger Crews and Longer Passages
When a couple becomes a family, or a cruising yacht becomes a liveaboard or charter boat, 20 LPH starts feeling tight. The LEDI Nomad steps up to 40, 60 or 80 LPH. It runs on 12 or 24V DC, and a 48V BLDC motor is available as a custom upgrade for high-efficiency setups.
- Output: 40, 60 or 80 LPH depending on configuration
- Integrated control panel with TDS monitor and flow meter as standard
- Cat Pumps 2SFSEEL 316-stainless high-pressure pump, compact direct-drive plunger, fully serviceable
- 2-stage pre-filtration, 316 stainless DEFLOK fittings, autoflush-compatible
- Weight: approximately 38 to 42 kg
- Pricing: see current pricing on the Nomad page
The Nomad suits liveaboards who want hot showers underway, charter operators who cannot afford rationed water, and larger crews on extended offshore passages. At those output rates, running the system for an hour or two covers a full day's water for four to six people.
What About a Below-Deck Modular Installation?
If you are doing a refit or a new build and want the watermaker out of sight, the LEDI Modular kit is designed for permanent or semi-permanent below-deck installs. It is configurable from roughly 10 to 80 LPH, includes a remote control panel and supports auto freshwater flush. Pricing is configuration-dependent, so contact the team at info@ledi.com.au or call +61 494 562 668 for a quote.
Power: Running a Watermaker on Solar Alone
One of the most common questions from cruisers is whether they need to run the engine or a generator to power a watermaker. For the Scout, the answer is no. At 12V and 16 to 18A, a normal house battery bank with 200 to 400W of solar runs it comfortably. Most cruising yachts that are anchored in good sun can produce water off solar alone, which is a meaningful cost and noise saving over thousands of hours of use.
The Nomad draws more current given its higher output, so your power setup needs to match. The team can advise on the right configuration for your battery bank and solar. For more on power requirements, see Can a Watermaker Run on Battery Power?
Maintenance on a Cruising Yacht: What Is Actually Involved?
The routine maintenance on a cruising yacht watermaker is simpler than most people expect. There are two things to stay on top of:
- Pre-filter cartridge: The Scout uses a 5-micron 2.5"x5" cartridge. In clean ocean water, replace it roughly every 30 to 40 hours. In silty or dirty water, sooner, roughly every 10 to 20 hours. The replacement cartridge is inexpensive. Quick swap, no tools needed.
- Freshwater flush: After every use, flush the membrane with fresh water. This prevents salt crystals forming in the membrane and is the single biggest thing you can do to extend membrane life. The Scout includes the hoses to do this. See Watermaker Flushing: How Often, Why It Matters for the full guide.
- Membrane pickling: If the unit is going into storage for more than a few weeks, pickle the membrane in a preservation solution. A maintenance chemicals kit is available from LEDI.
The RO membrane itself is not a routine consumable. With proper care it lasts several years. LEDI offers a 1-year warranty, extended to 2 years on registration, and lifetime in-house servicing from the Gold Coast. Spare parts post Australia-wide and internationally, typically within one business day.
Frequently Asked Questions
What output rate do I need for a cruising yacht?
For a couple on a 20 to 50-foot yacht, the 10 or 20 LPH Scout covers typical daily needs. All LEDI watermakers are sized with continuously rated pumps, so there is no fixed run-time limit; your water needs and power supply set the run time. For a crew of four or more, or if you want showers underway, the 40 to 80 LPH Nomad is a better fit. Start with your daily water budget and work backwards from there.
Can I use a portable watermaker on a sailing yacht without installing anything?
Yes. The LEDI Scout requires no installation. Drop the stainless intake hose over the side, connect the supplied hoses to the unit, and you are making water within minutes. Nothing is plumbed to the hull or the boat's systems.
Does a cruising yacht watermaker need a generator?
Not for the Scout. It runs on 12V DC at 16 to 18A, which a standard house battery bank with 200 to 400W of solar handles comfortably. No generator is needed. The Nomad draws more current given its higher output, and power requirements vary by configuration.
How long does the RO membrane last on a cruising yacht?
With regular freshwater flushing after each use and proper pickling for storage, the membrane typically lasts several years. It is not a routine consumable. The main routine consumable is the pre-filter cartridge, which is inexpensive and quick to swap. See the full guide on watermaker membrane lifespan.
Talk to the LEDI Team
LEDI is a Gold Coast business and you deal with a real person, not a call centre. If you are not sure which system fits your boat and your plans, get in touch at info@ledi.com.au or call +61 494 562 668. The team will help you match the right unit to your actual daily water needs, power setup and budget, without any pressure.
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