Anodes in freshwater?

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

martyc

Veteran Member
Joined
May 29, 2022
Messages
39
Vessel Name
Sun Chi
Vessel Make
Greenline 33
I'm just about to haul out and this year we have been in freshwater. For the next few years it will be all canals and rivers. This page https://www.boatsafe.com/electrolysis-eat-prop/ includes a statement about using magnesium or aluminium for fresh or brackish water instead of zinc.
Any thoughts?

Cheers, Martin
 
My thought is a strong vote to follow that advice.
Zinc us useless in fresh water. I've changed everything to alum as I'm in FW full time.
Don't forget the engine & cooling system zincs.
Alum is getting easier to find as many are switching over.
Side power thrusters only sell replacement Alum at least for my thrusters.
 
I'm just about to haul out and this year we have been in freshwater. For the next few years it will be all canals and rivers. This page https://www.boatsafe.com/electrolysis-eat-prop/ includes a statement about using magnesium or aluminium for fresh or brackish water instead of zinc.
Any thoughts?

Cheers, Martin

Yes!

I use aluminum as I spend about half the year in freshwater, a third in brackish water and the balance in salt water. While magnesium is better than aluminum for freshwater, it's only available in a relatively few sizes. Aluminum will work in freshwater and works in everything else.

Ted
 
Yes!

I use aluminum as I spend about half the year in freshwater, a third in brackish water and the balance in salt water. While magnesium is better than aluminum for freshwater, it's only available in a relatively few sizes. Aluminum will work in freshwater and works in everything else.

Ted


Agreed. I've been using aluminum as well with good results in fresh water (Lake Ontario). Unless you have any really hard to protect metals or you're in extremely clean fresh water, magnesium is probably not needed.
 
Great article! Thanks for posting it!

I agree with the Aluminum recommendation for salt + brackish waters, as I have been told as much by several yacht yards over the last three years here in the Med.

This after having gone through France in canals and rivers in 2019 blissfully ignorant that the zinc anodes I had on from Sweden were no longer providing any protection. Ended up with a pink-ish prop.
 
Last edited:
Back
Top Bottom