Ok i have view a couple treads on here about people wanting to coat there diy rock background with resin. The question was asked " what is a safe resin to use" but no one gave a good answer. I recently made myself a fiberglass background after seeing someone on youtube doing it. Mines came out great got it painted with the "look like stone" spray. Now im stuck, because the last step is a problem. For the next step i am supposed to seal the background with a coat of resin. Came to find that a few people are saying that resin can leak chemicals, and kill your fish. Now i ask the question again.. What is a safe resin/product to use that will clearcoat/seal the background? I found this stuff in the craft store (Castin'Craft Clear Polyester Casting Resin) any thoughts on this product? I see folks making plywood aquariums, what resin are there using? I when to the local fiberglass supplier, and they was not much help.