Tank Not sitting Flat!

[Octoberfest]

I'm filling my new tank and noticed its not sitting flat on the stand. The tank is a 200 gallon acrylic tank. I have it sitting on 1/2" Styrofoam and the two front corners are not putting pressure on the foam. It's close but I can still see light between the tank and the foam. The tank is only about 1/3 full.

I've filled acrylic tanks in the past and the leveled out once they had enough weight in them but I just want to be sure before I continue filling this one.