If it were me, I would make sure all sides of the tank are supprted. Either by adding another board to the inside of the stand to surrprt the side with a gap or some other method. A 115 tank is a sizable investment and I'm sure you don't want to clean up that much water on the floor. I know I don't.
If the boards happen to be bowed, you could sit the tank on 1/2" insulation panels and allow the tank to find its own resting place. Hope this helps.