Determining floor/joist weight capacity

[newreefer_59]

I am getting some great responses here. To answer Triggerman: The actual tank is 60X24X24, so without anything but water, it is 148 gallon PLUS a 56 gallon sump under it that would be half full I imagine at any given time. There is already a 3/4 " sheet of plywood under it and the joists are 12" I-Beams. There would not be any major partying around it as it is in a library type room and against one wall as well. I will attach a drawing.