that is the question. Red Sea reefer 250 is out of level front to back. Put shims underneath it and I was not comfortable with the way it feels. Red seas cabinet has plastic feet I shin it and they are off the floor in the middle of the cabinet. However there is a foam pad underneath the tank itself and the tank is current empty. If I add the weight of the water will said foam pad compress and help the tank “self level “ and suggestions greatly appreciated.