[tinman]

i just go to home hardware and purchase tubes of their brand (weather shield) 3 tubes for 20 bucks, maybe it is ge, don't really care says right on the tube safe for aquariums been holding back 200 plus gallons of water and rock so far. i've used it on all sorts of aquariums for years and never had any trouble, call me crazy but i know what works for me. just my 2 cents.