15MM Whale Fittings??

[brk-lnt]

To answer your question, yes, I've done a few marine freshwater systems. Convert everything to locally available 1/2" PEX. Try to avoid any metal components, use the push-to-connect plastic fittings wherever possible.

While you're at it, add some extra fittings to make draining/winterization easier if you don't already have these.

Also, a run timer on your fresh water pump with an auto-shutoff might dave you future hassles if a connection comes loose and you pump drains the FW tank into the boat, and then runs endlessly.