Need help with a white buildup on a fish tank

[The amazing Catfish]

AS the title says i have a white buildup on the glass. it comes from my water and i cant seem to get it off the tank. the tank in question has been empty for a while and ive been trying to get this off for months. I've tried CLR and regular soap on it to no effect. any advice?

 

[Columbian Shark 3]

White vinegar

 

[The amazing Catfish]

Ill give that i try thank you : )

 

[BODYDUB]

I was in the same boat as you a couple of months ago. I used EVREYTHING to include taping a wet piece of a paper towel soaked in CLR overnight with no results. I ended up selling the tank which I hated to do.........

 

[iloveoscars702]

eh my 125 was like that when i got it off craigslist, not problem since you cant see it when the tank is filled with water

 

[boldtogether]

White vineger, heated if possible. The hotter the better but dont shock the glass or it could crack.

 

[johnny potatoes]

try the vinegar and scraping with a new razor blade

 

[The amazing Catfish]

eh my 125 was like that when i got it off craigslist, not problem since you cant see it when the tank is filled with water

i wish mine wasn't visible. but it is. all down the side(s) and near the rim.

and as a general note thank you guys for the advice. i will try the white vinegar when i can buy some.