Ugh... I feel your pain. I conscientiously clean the glass with the mag-float and work very hard at preventing scratches. Under normal circumstances, I am the only one who ever touches the magnet.

But my job sends me traveling quite a bit, sometimes for six or eight weeks at a time. And during those times, when I'm away and Mike comes to visit me, my mother has been good enough to keep an eye on everything from the fish tanks, the dogs, the cats and our two teenaged girls. So I bite my tongue (HARD!) and say nothing when I come back from my travels to a couple of new scratches on the glass as a very special "souvenir" from my trip. There are quite a few now from the past three years. I just try to be grateful (to have the support from my mom and to get to do some traveling) and then I dream of my next tank, which will have no scratches, no hidden killer crabs, no LPS-nipping flame-tailed blennies and free from cyano (hey, as long as I'm dreaming!). Someday...

Hope you figure out a way to get the scratches out without having to drain the tank, Jose.