Zinc vs Navalloy for brackish waters

[lancelot9898]

In the past I've used zincs for anode protection, but reading info from USAzincs.com indicates that a navalloy alloy is best for the Chesapeake Bay. Has anyone out there made the switch to navalloy and what were the results for people here on the Chesapeake?

[a64pilot]

What is Navalloy?
I have switched to aluminum, cause I spend considerable time in brackish water.

[lancelot9898]

I suppose it's some sort of Al alloy marketed by usa zinc website. How is the Al doing? I've always used Zn here on the Chesapeake and I'm considering switching if there is a better option.

[thinwater]

This testing was run mid-Chesapeake, with the intension of studying brackish water:


https://www.practical-sailor.com/iss...l_12144-1.html

[fstbttms]

https://performancemetals.com/pages/...luminum-anodes

[a64pilot]

Originally Posted by lancelot9898

I suppose it's some sort of Al alloy marketed by usa zinc website. How is the Al doing? I've always used Zn here on the Chesapeake and I'm considering switching if there is a better option.

I prefer the aluminum, it does seem to last longer.
I see no downside of it, even if only pure salt water. Plus it’s not a toxic metal, zinc apparently is.
When in brackish waters, zinc seems to form a whitish layer on it, looks like calcium or something. I suspicion this whitish layer may degrade the performance of the anode, aluminum doesn’t form this layer.

[jen1722terry]

Interesting thread. I always use zinc unless I'm moored all summer in brackish
water. Interesting quote below from Martyr Anodes, one of the larger makers of anodes:

"Freshwater Anodes. Yes, corrosion does happen in fresh water but generally at a slower rate. ... A magnesium anode is a super activated metal which means it will protect more efficiently in fresh water. Traditional zinc or aluminum anodes are just not effective as they do not produce the voltage necessary to work properly.
Freshwater Anodes | Martyr Anodes
martyranodes.com/freshwater-anodes"

Cheers!

[fstbttms]