More information please. What type of boat? Power available? Water
There are two schools of thought.
1. High volume high power requirements.
2 low volume low power
We have one of each installed on 2 separate boats.
On our smaller mono we chose option 1.
We installed a cruiseROwater system. It produces about 30 gallons an hour is modular and they have great customer support. In 2 hours we fill our main tank using this system and a Honda
2000i portable generator
On Our cat it is option 2. The cat has a much bigger battery
bank and can produce 6-7 gallons an hour on just battery
power with a little wind
keeping it going. This system is a spectra 150 and works great no complaints.
Installing either system requires some thought to make the installation
easy to use and maintain. You will need a dedicated through hull
Hope this helps