Re: best way to mount Aluminium to steel underwater
noelx77 is correct, done improperly this could sink your boat.
"electrolysis" is not the issue. Electrolysis is the chemical change in a solution or electrolyte due to the passage of electric current.
The potential problem here is "galvanic" corrosion and mixing steel, aluminum and DC current under water could cost you big time if not done properly. I strongly advise you to consult an ABYC certified electrician before proceeding.
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