Too Many Anodes
Its a question that that can be difficult to answer: how many zinc should I have. While the rule of thumb I use is 2 zinc per shaft where space allows, Generally, there shoud be 1 per every 2.5 feet of shaft. The amount of charge from bi-metal efffects and stray direct current varies from boat to boat. What counteracts, or balances the charge is the amount of Surface area on the anodes. If you have too much, you are building up an excessive charge on the anode's end, where the cathode's charge is again out of balance, where by those metals are no longer protected.
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