Slanted floor

[treesprite]

What's the best thing to use shim one end of a tank stand? I just moved to a 15th floor apartment, and the entire concrete slab is at an angle widthwise, going towards the balcony (which is around 25ft long, enough to roller skate on). According to the roller skate,  there is no lengthwise angle, but I have to find my level to be more accurate.

[Jon Lazar]

How about a composite or rubber furniture shim:

 

[treesprite]

It's going to have to go the width of the tank stand, or most of it. 

 

[Jon Lazar]

You can place them side by side, along the width of your stand.

 

IME the best way is to install adjustable feet.  If your stand is built properly, you don't need the whole length of the stand resting on the ground.  It's the same concept as a framing header above a sliding glass door.