how to get white film off glass?

[cherokee933]

ok..so i have this old 10 gallon that was used a while ago as a sump and i cleaned it out and there is the white kinda film that won't come off unless you scrape realy hard with ur fingernail or something. Any ideas how to get it off?

 

[bassmaster]

I had very similar stuff when i bought my 20 gallon. It's "hard water" or the stuff in water that when it evaporated was left behind, and after a few years of it, became visible.
Try a scraper of some sort. Just be careful not to scratch your glass. After a few hours of work, most of it should be scraped off. Wash it out and look at you shiny new tank!

 

[denisec]

I'd think some spray bathroom cleaner would do it. But you'd have to make sure you cleaned it super good after that to get that off. But might save you some scraping.

 

[viking]

Try CLR they stuff gets off everything!!! but you have to rinse the ever living hell out of the tank afterwords!!!

 

[fender]

Try using just plain vinegar(sp) it should dissolve the buildup, especially if its calcium. Rinse real well when you're done.