Removing coraline algae from empty glass tank

[TaiChiPlayer]

Does anyone have any tips for removing old coraline algae from a tank? The stuff seems like concrete!

 

[sir_dudeguy]

soak some vinegar on it and get a razor blade

 

[papagimp]

Razor blade and elbow grease.

 

[TaiChiPlayer]

Thanks for the tips! FWIW a guy at my local fish store recommended muratic acid (most swimming pool places have it). It was a 24g aquapod. I dumped a gal in it and let it set overnight. The stuff came right off with a metal scraper. Pretty nasty stuff to work with but it sure did the trick.

 

[Konadog]

FWIW, Vinegar will work just as good, and is a lot easier to deal with when trying to clean up. I usually lay the tank on its side, dump in just enough vinegar to cover a pane of glass and let it sit for a few hours. Scrape, clean, and repeat for each side.