What Goes Under The Antifoul On Fibreglass Hulls?

[charliehows]

having a bit of trouble getting decent info - on my last antifoul i noticed a few spots of exposed f/glass which i spot primed with the primer from same mfr as the antifoul paint BUT - not feeling confident that this is a satisfactory treatment for the problem.
what have other people done and what is the best treatment/product(s) for this sort of thing? Note; I'm talking about below the waterline on a 35 year old hand laid fibreglass hull with no osmosis or other signs of deterioration.

[leftbrainstuff]

Gelcoat

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[SailFastTri]

The ideal coating is epoxy barrier coat