Interlux Primocon Underwater Marine Primer Primacon is an anti-corrosive primer for all underwater metal surfaces. It will provide an excellent barrier to reduce pitting caused by galvanic corrosion. For non-aluminum underwater metal use any non-vinyl_ Interlux antifouling paint. An excellent primer for antifouling paint over sanded fiberglass. Primocon can be used as a conversion coating over unknown well-adhered antifouling paint to prevent cracking of new antifouling paint. Primocon will not