Yesterday I felt the glass bottom of the tank under the mulch where the heater is stuck and was alarmed to discover it was hot to the touch. The mulch was nice and toasty, but the glass under it too hot to leave my hand on. I didn't realize the tank needed to be elevated so there was space between the floor of the tank where the heater is stuck and the furniture. Yeah, I know, duh. I propped the tank up on some dominoes and ran out to get the thermometer I'd been meaning to get. Even after elevating the tank, the thermometer still read over 90 on the inside glass on the bottom of the tank. Of course, Gilbert frequently burrows under the mulch, and I was concerned he could get burned. I pulled the heater off of the glass and let it lay on the table under the elevated tank. Now the glass bottom is 83 deg, but the mulch doesn't feel very warm. Is it warm enough if it doesn't warm the mulch that much? There was a thermostat that I could plug the heater into for sale at Petco, but that sucker was $80.