When it came to re carpeting our old house, I didn't want to move my 350 Ltr Tank so the Carpet Layers cut around it, laid the new carpet upto the tank and we kept the piece that would have gone under the tank.
When it come time to move to the house that we built, once the fish tank was moved into the new place, we got the carpet layers back to lay the piece where the Fish Tank had been, worked a treat.
Good Luck
Lynda