I'm not sure how dumb of a question this is, but I'd like to now if it's okay to use a bronze sculpture in my freshwater aquarium. The only fish in there will be a single goldfish, and I saw a lovely bronze statue to add to my aquarium. Will the statue create any chemicals in the tank that could kill my fish? If so, is there some sort of waterproof or weatherproof stuff I could coat the sculpture with so that it doesn't harm my fish? What other materials are no-no's for tanks?