So I have a question for the 'brains trust out there. My latest project boat is aluminium hulled(plated in 5083 grade) and we made a skin fitting for the engine water intake out of a solid billet(probably structural grade?).

My concern is I'm worried it might eventually 'fizz up' in the salt water. I do not like plastic skin fittings under the waterline and on any other boat or yacht, I would normally replace with bronze or S/S.
That is okay on a glass or wooden vessel, but aluminium has no other compatible metals that I'm aware of either.
Can't get hold of any marine grade aluminum skin fittings.


Which way do I go with this?-Cheers CR.