Used Tank...Calcium buildup

[Psychodreamer]

This may come across as a stupid question, but I bought a 29 gallon tank used recently which has some calcium buildup. The lady, who is a friend of mine cleaned it as much as she could before giving it to me, but she was afraid to use any razor blades or scrapers on the glass. My question is this, what's the safest way to get this buildup cleaned off without using cleansers which could leave chemical residue in the tank? Thanks in advance for any advice!

 

[IovaykInD]

Try a dry towel, don't use wet ones. It worked for me.

Isaac

 

[Tolak]

Vinegar works well. Rinse with water after use. I've used it on more things than I can list.

Tolak