you can use shims on the carpet side to level the tank. Otherwise you take the chance of damaging the stand and/or tank because it will begin to sink on the carpet side but not on the tile side (you might even damage the tile b/c of the weight). Try a test run by just filling the tank with a hose and tapping in shims under the carpet side to keep it level while filling. Lay level across the top and tap in shims along the bottom. When it's full of water and level just cut off the shims. It might sink a little more with gravel and rock but you can just tap the shims further in to adjust. When your done cut any exposed shims off with a utility knife. Nice tank.