Anode material type and water type and stray electric "heat" of the docking area and boat-batt system should all be well considered.
IMHO: When there is no anode surface scrubbing provided in fresh water then magnesium is best to use in fresh water and zinc is (always) best to use in salt water. That said, if and only if the zinc surface is scrubbed clean of oxidation (by scraper and bronze wire brush every 3 to 4 month or sooner) can the zinc stay active enough as a functioning anode in fresh water.
Stray electricity “the heat” from a dock or area may be slight, medium, or severe, depending on electric power cord conditions in the area. “Hotter” the area’s stray electricity is then faster the anode disintegrates, “cooler” the area slower the disintegration. Also keep in mind stray DC current off boat batteries; metal items also need to be bonded/protected against that possibility of corrosive stray current.
Fastbottoms is the TF pro on all this about anode/diode. I’m not expert on this but know a bit. I don’t want to lead you astray and hope fastbottems soon posts.
Hope there has been little damage to now!
IMHO: When there is no anode surface scrubbing provided in fresh water then magnesium is best to use in fresh water and zinc is (always) best to use in salt water. That said, if and only if the zinc surface is scrubbed clean of oxidation (by scraper and bronze wire brush every 3 to 4 month or sooner) can the zinc stay active enough as a functioning anode in fresh water.
Stray electricity “the heat” from a dock or area may be slight, medium, or severe, depending on electric power cord conditions in the area. “Hotter” the area’s stray electricity is then faster the anode disintegrates, “cooler” the area slower the disintegration. Also keep in mind stray DC current off boat batteries; metal items also need to be bonded/protected against that possibility of corrosive stray current.
Fastbottoms is the TF pro on all this about anode/diode. I’m not expert on this but know a bit. I don’t want to lead you astray and hope fastbottems soon posts.
Hope there has been little damage to now!
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