I have an AP T8 heated only by one of Pro Products RHP's. It's on one side of the tank being controlled by a thermostat. I have my thermostat probe on my cool side so the RHP kicks on when the cool side get's too cool. This provides the basking spot, or hot side, for my girl and regulates the temp of the cold side. My tank stays at 90-93 for the hot side and 76-79 cool side. I didn't think belly heat was necessary and my BP is perfectly happy, eating regularly and having 1 piece shed's. My thought process was that they don't have belly heat in the wild, so if I have a hot side and cool side she's going to be fine.