i got a 150g 4'x2'x2'6" tank and the only thing stopping me from filling it is that it is slightly tilted forward (with 1 gallon of water) only the back L is exposed about 6". i really don't want to crack this tank and was wondering how you level a tank. i realize i could put some wood under the stand but was thinking that might cause some pressure points wherever the shims are. was just looking for advice how to make sure the weight is distbursed uniformly. thanks