Please help to fix my crooked stand

[Casey8]

I built a crooked stand that was custom made by ME, and please don't ask me for the picture I was hoping when I let it sit on the carpet and fill up the tank with the water it will be OK, but it is not. One side of the tank is about more than half an inch lower of water than the other side.

I need help from some handyman here, please tell me what to do to make it more levelling without tearing this crooked stand apart to redo it.