Originally Posted by Kai Wolf
I did eventually decide to just buy a new one for this project. Figured it wasn't worth the headache! But now that the pressure's off, I will try the razor blade on the old tank. Should I use it dry, or toss some vinegar or something on there while I scrape?
I cut a lemon in half and scrub the glass, followed by razor blade over wet lemony surface. Etching is etching, though, and if those aren't just hard water deposits then nothing short of buffing the glass will work.