I once moved a full stocked 75g (stand, sump, lights- everything) about 10 feet, but the pumps and lights were only off for the 10 seconds it took me to change outlets.
I used those little furniture mover pads they sell at home depot - just slid them under the corners (using a crowbar to gently bring the tank up the 1/4"), and it slid without too much effort. I didn't use the biggest ones, but I'm sure you could move a much bigger tank like that.