cleaning a used tank

[merc1500]

i got a free ten gallon tank here in front of me i have cleaned it really well but i have this white fil at the top and nothing with take it off trid razor blade no change is there way to get this off

 

[Lotus]

Try some white vinegar. Either pour it on, wait a few minutes and use the razor blade, or put it on a plastic dish scrubber and scrub away. Rinse well afterwards.

 

[DesignsOnYou]

They also make aquarium cleaner. You can but it at your LFS. I haven't had much luck with it, but I was trying to get off something especially difficult. I'm not sure how anyone else on here feels about it.

 

[TMony]

I have used the "safe and easy aquarium cleaner" available at most pet stores.
If you spray it on and let it sit for a awhile and then go at it with a razor blade it seems to do a nice job.

Here's a link

Aquarium Pharmaceuticals Safe & Easy Aquarium Cleaner at PETCO

 

[tom91970]

Lime Away works good, too. I bought a used 55g tank and that was the only thing that worked on some of the tougher spots.