Okay, the floor not level because of foundation and shimming the tank to correct it is one thing, but the tank being out of level because of the stand is a big problem. Do you have a level? Check the floor, and then check the top of the stand, and then check the top of the tank. Compare them to figure out what is level and what is not. The stand HAS to be level. I had a 210 crack the front pane a few months ago, I'd hate to see the same thing happen to you. It took 5 weeks for the tank to fail, but it did.

I'd offer you a 55 to help save some of the water but I see you're not really close.