So i found the comapny that makes the Liquid rubber in the States... they are called Perma dry (1-800-279-5604).. So i talked with the guy for a while yestreday, and he said he "KNOWS THE PRODUCT IS NOT HARMFUL TO FISH"... he said the only thing is does is turn a dark shade of brown (almost black) when submerged in water. it starts off brown and dry's black... It is still completely dry when it turn the almost black/brown color... its just what the product does... So im going to order a gallon of it this weekend and test it out....