I recently lost my betta and yesterday I drained the tank. I want to repurpose it into a terrarium with some venus flytraps and such but the tank smells and is grimy. Almost a year of hard water stains and overall tank detritus have left their mark. For the smell I figure a satchel of carbon should do the trick. As for the rest of the tank, I was thinking denture cleaning tabs. Hear me out here! I was reading a thing that said you could use denture tabs for cleaning toilet tanks, diamond rings, and to get hard water stains out of a flower vase. Flower vases and aquariums are both glass and both hold living things so it should work, right? My only concern would be what the tabs are made of. But if people use them to clean things that go into their mouth, it should be safe. I'd like to hear anyone's thoughts (or alternative ideas) on this.