Get some oxytetracycline from your veterinarian, make a powder of the
crystals and add it to the paint near any 'problem' areas where
barnacles attach to the paint. Effect will only last a season.

I also think the oxytet is commercially available .... called
"Compound-X" etc.; available from BoatUS/WM, etc. but expensive.



In article , Karin Conover-Lewis
wrote:

Interesting tip, Rich. Explains why the bottom paint is just plain gone at
my lower gudgeon, which has a tear-drop zinc attached to it. Diver must have
been scrubbing that area vigorously. I'm planning to give that area several
coats when I repaint the bottom next year (on the hard this year).