Lime deposits on used tank?

[elwallacejr]

Hi Folks,

 

I'm the proud owner of a new to me but used tank.  I gave the tank a good vinegar bath/scraping and got the vast bulk of the calcium deposits off.  However, I have not been able to clean off the film that was primarily north of the water line.  I've included a picture but was wondering if anyone has any suggestions for getting this stuff off.

 

Thanks for the help!

[AlanM]

If vinegar didn't do it, it might just be etched?

[elwallacejr]

If vinegar didn't do it, it might just be etched?

Really hoping that isn't the case but that won't change my mind on the purchase.  Nice step up from the 40 Breeder.

Edited November 28, 2016 by elwallacejr

[sethsolomon]

try a razor blade?