Zinc fish

[sailawaylater]

There is a back core to my over the side zinc "fish". Is the black core sacrificial anode like the outer zinc material that seems to be close to fully gone?

[osirissail]

I would say no - the core is what the zinc is moulded around to keep it slipping off the wire.

[Cheechako]

wow, I had no idea they werent solid zinc.

[Paul Elliott]

Here's a different question about Zinc fish: I have one over the stern, with the clip attached to my grounded backstay chainplate. It has been getting coated with a white plaque, I assume Zinc Oxide. I've read that this can happen in brackish water, but we're in Friday Harbor, which is pretty salty. Any suggestions?