Hard water etching?

[Skrippdaddy13]

Thanks cermet, but it is definitely glass. Not soft like plastic soft, but if you continue scraping away at a stain and dig an edge of the razor in, the glass will begin to scratch deeply. Also I noticed when it's wet the stains on the inside vanish and then reappear when dry. Hopefully these won't be seen when tank is filled with water? There is a bad one outside that looks like drip-marks. I tried limeaway on this outside surface, and it helped absolutely zero! Even after soaking for awhile. If limeaway won't even touch it, then it must be stained in the glass right? Permanent? Etching? Buy some muric acid? Buff or polish? Or just use as a spare ugly tank?

[Lady Hobbs]

Why not save that area for the back of the tank? Some of the products talked about here just might weaken the silicone sealant.

[sir kyle]

im guessing that u r using a brand new straight razor. the angle of the blade should be almost flat to the glass, maybe just a finger on the glass to hold the angle.

[Skrippdaddy13]

Thanks hobbs and thanks sir kyle. This tank is driving me ape poopie!!!!! The stains are on all sides of the glass, inside and out. It really looks like mineral deposits from hard water neglected over time to me. ive been trying everything on the back panel, on the outside. hot vinegar soak, limeaway, aquarium salt scrub, praying to a higher being, and even went so far as trying muriatic acid on a small area. NOTHING! NOT EVEN THE SLIGHTEST REMOVAL OF ANY STAINS!!!????? Is it just crappy glass, or is all aquarium glass created equal? ive taken a razor to this thing in all of these steps, and it does nothing!! 99.9% of old tanks can be cleaned up, but of course i bought one that couldnt be. I give up i guess. gonna let it dry well, run my new rtv silicone, let it cure for a week, leak test it, then throw some t5 ho lights on top and see how it looks. I notice the inside stains dissapear when they are wet so i gotta get lucky, or im just gonna give it away . and to add to it, late last night when i was trying to shift this beast around, my dang hand slipped and i caught the raw glass on the top with my big stupid thumb!!! Drove to the E.R one handed at 1:00 a.m. to get 8 stitches!! Im just having a grand ol time with this damn thing!! thanks everyone for all your help and input, but if straight muriatic doesnt touch it ,i think its doomed!! hope it looks better enough full of water and plants!