Aquarium sealant would be fine. Most epoxies, while nontoxic when fully cured, aren't really made for constant submersion, unless specifically designed for it.
And something that really bothers me is people who start criticizing others when they ask about a way to save money. Maybe they have won the lotto or something and cash doesn't mean anything to them, but some of us work darn hard for what we get, and I for one will take any reasonable means I can find to save money as long as it doesn't compromise the health of my animals. That way I have more when the need for things does arise. It's stupid to waste cash you don't have to.