What size watermaker for a fishing boat?

Include deck washing, not just crew use. Four crew at 40 litres a head is 160 litres a day before wash-down, so 100 to 240 L/hr is a realistic range depending on the job.

Can a watermaker handle harbour water?

The intake should be placed to avoid contaminated or silty water, and prefilters will load much faster than in clear ocean. Making water while working in a river mouth or a busy harbour is not recommended.

Is a watermaker worth it on a workboat?

It depends how far you run and what carrying water costs you in tankage and time. For boats working several days offshore it usually pays; for day boats returning to a wharf, usually not.

By vessel · updated 5 September 2026

Watermakers for fishing boats

On a working boat, fresh water is consumed by the job as much as by the crew: washing down, rinsing gear, topping up. Demand is high and lumpy, and the boat usually has machinery running anyway.

Typical daily need160 L4 aboard at 40 L each

What to optimise forLitres per houron this kind of boat

Shortlist leaderRainman Frame AC 240L Torrent, auto0.7 h and 2,018 Wh for 160 L

Schematic, not to scale. 4 aboard at 40 litres each is the planning figure for fishing boats — 160 litres a day. The shortlist below runs on 12/24/48 V DC, 240 V from a generator or a petrol motor.

The power reality. Most working boats have generator capacity or a large alternator, so the kilowatt-class systems are viable and give the best output per dollar.

What matters on fishing boats

Deck washing dominates

Crew drinking and cooking is a small share of a working boat's fresh water. Size from the whole job, not the galley.

Dirty water is hard on prefilters

Working close inshore, in river mouths or around a busy harbour loads filters far faster than clear ocean. Budget for that.

Vibration and mounting

A workboat is a harder mechanical environment than a yacht. Mounting, hose support and chafe protection deserve more attention than the spec sheet.

Simple beats clever

Manual controls that a deckhand can operate and a skipper can diagnose often outlast an automatic system on a working vessel.

Narrow it by what you can power

12 V DC6

Shortlist for fishing boats

The 8 best matches of 29 that suit fishing boats, ordered by litres per hour. Run time and energy below are for 160 litres a day.

System	Power	Output L/hr	Draw W	Wh per litre	Price
Frame AC 240L Torrent, auto Rainman	AC 240V	180–264	2,800	12.6	$15,089
Frame AC 240L Torrent, manual Rainman	AC 240V	180–264	2,800	12.6	$12,089
Performance Triple 200L · 12V feed Water Makers Australianameplate estimate	AC 240V	200 nominal	1,610	8.1	$9,181
Automatic Triple 200L · AC feed Water Makers Australianameplate estimate	AC 240V	200 nominal	2,280	11.4	$19,250
Zen 150 Schenker · spec unconfirmed	12/24/48V DC or AC	150	—	not published	on request
Performance Double 140L · 12V feed Water Makers Australianameplate estimate	AC 240V	140 nominal	1,610	11.5	$7,791
Portable AC 140L Rainman	AC 240V	100–154	1,250	9.8	$5,329
Portable Petrol 140L Rainman	Petrol	100–154	—	petrol	$6,731

Under 6 Wh/L · energy recovery

6–12 Wh/L

Over 12 Wh/L

Check it against your own boat

Enter your crew, battery bank and daily solar surplus and we will show which of these actually fit.

Open the calculator

Common questions

What size watermaker for a fishing boat?: Include deck washing, not just crew use. Four crew at 40 litres a head is 160 litres a day before wash-down, so 100 to 240 L/hr is a realistic range depending on the job.
Can a watermaker handle harbour water?: The intake should be placed to avoid contaminated or silty water, and prefilters will load much faster than in clear ocean. Making water while working in a river mouth or a busy harbour is not recommended.
Is a watermaker worth it on a workboat?: It depends how far you run and what carrying water costs you in tankage and time. For boats working several days offshore it usually pays; for day boats returning to a wharf, usually not.

Guides that go deeper

Other vessels

Not quite your boat?

charter boats motor yachts boats off-grid and expedition use

How the shortlist is built. 160 litres a day is 4 aboard at 40 litres each — a planning figure for this kind of boat, not a measurement of yours. The list is filtered to systems whose power source suits fishing boats and ordered by litres per hour. Every figure is the manufacturer’s rated output and draw; Wh per litre is one divided by the other. Where the closest Water Makers Australia model falls outside the normal power filter, it is included as a disclosed 240 V Australian alternative. Methodology.