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Zinc Anodes in Fresh and Sea Water

2001

I've got a question !

I own a 32' fibreglass sailing boat and have a zinc anode fitted to the prop shaft. The boat is kept in a marina which is gradually being turned to fresh water (as part of a barrage scheme in S Wales (UK)). I then sail the boat in seawater and I'm told that my anode will not perform properly in fresh water. I am also told that I should get a freshwater anode (never heard of one though) to combat the problem but that I should expect this to sacrifice very quickly in seawater.

In this right ? - Any advice

Thanks

Ken Pugh
- Panarth, UK

We are producers of zinc, aluminium and magnesium anodes. Zinc will not work in fresh water it is purely for salt water. Magnesium is the simple answer to your problem with fresh water, although magnesium needs to be removed when going into salt water for long periods. Therefore if you connect magnesium anode to a length of conductive wire and made a crocodile clamped connection to what your trying to protect and simply leave your zinc anode on and connect the magnesium to the shaft whilst your in fresh water.

Peter Foster
- Kent, England
2002