Cleaning tank glass removing red SW algae, need some help.

[Cookie*]

I picked up a used 90 gallon SW tank and I'm making it FW. Everyone told me removing the red algae with a razor was the best move, and it was for the bulk of it. But, underneath where all the algae was that I scraped off, there's mineral spots all over the glass. It only millimeters thin and looks like dried water but it's hard and cannot be scraped off or removed with a vinegar solution. I soaked the side glass for about a hour in a 1/2 vinegar X 1/2 water mix and it did nothing.

Before I go crazy and whip out some power tools to try sanding or grinding it off with some steel wool, does anyone have any better suggestions? I don't like the steel wool idea I'm tempting myself with. It could get ugly. I just want the glass as clear as I know it is, there's no scratches and hopefully I'll keep it that way.

 

[mpr163]

stay away from the steel wool! i ruined a tank thinking diamonds were the only thing that could cut glass. try the vinegar 3/4, it wont hurt anything, let it soak longer, and pick up a pack of scrub pads from the store, i got 2 for 99 cents. This process has only failed me once, on a tank with 10 year old calcium marks. good luck!

 

[Cookie*]

This tank had water in it yesterday so hopefully it will work with just a longer soak in the vinegar solution. Thanks for the heads up on the steel wool too. I'd rather have a tank with a lot of calcium deposits than a tank with a lot of scratches, if it should come down to that.

 

[Cookie*]

I tried vinegar and CLR, both did nothing. I'm convinced glass cannot be cleaned if the stuff has been stuck to the glass long enough.