How to remove stains from tank

[USMA36]

I'm resealing my 210. There are some pretty serious stains on the inside glass behind where the overflow boxes go. There's also a mark on the glass from an mp 40 that I can't remove. I've tried straight vinegar and scraping with a razor with no luck.

 

[KrisReef]

Denatured alcohol is the best glass cleaner.

 

[fishguy242]

hi have you tried soaking towel with vinegar,laying on for 5-8 hrs,could do the trick,
2nd would be muratic acid ,but be very careful ,do not breath,get on skin ,vapor in eyes,then wash down with baking soda,to nutrulize ,then alcohol before resealing... hope vinegar rag works first!! "CAREFUL W ACID"

 

[fishguy242]

Denatured alcohol is the best glass cleaner.

will that remove the hard water marks?? have never tried??

 

[KrisReef]

will that remove the hard water marks?? have never tried??

I think your method is probably more likely to get at hard water-marks. I have never had much luck removing stains.