i already am going to do this, my room is above the chimney which would be 2.5ft of the tank beneath it so what i am going to do is put the tank so its 2.5ft on concrete and 3.5ft on joists. it will also be perpendicular to the joists and up against a wall.
You would have to have five people over 500 pounds each to weigh what my 180g setup weighs