my newest tan 72x24widex18 is refusing to go below the high 80's like 89 most times. i took the heaters out of the tank, the lighting is 48" qaud tube flourecent and running 2 emporer 400's and a small air stone. it never gets direct sunlight heck it is next to a north facing window that stays open. the light hangs about 8" above the tank with no canopy just plexi lids. its heating my whole crapin house up and its already claimed my lima.
the pumps sound like the only heat source if the lights are off and heater unpluuged