Proper sealant for glass to fiberglass
I am working on a frog exhibit to display several species of native frogs. A sculptor is creating some fiberglass bases, which will be sealed with a urethane gelcoat. I want underwater viewing for 4 shallow pools and wondered what sealant is best to bond the two surfaces together without leakage. Also want to be certain to use something that will not give off any toxins. Aquarium sealants all seem to specify glass to glass only. Any thoughts?