Makes perfect sense, dimmers change the heat but need to be contorlled by you. What I am looking for is a "Set it and forget it thing" I currently have 2 dimmers from home depot, one for hot side and one for cold side. They work fine, but for instance when I go to sleep at night, by body heat can change the temperature in the room to at least 4 degrees higher, thus increasing the tempertaure in the tank 4 degrees high, just as you said. What I was looking for is something that will keep a constant temperture in the tank no mattter the temperture in the room so if I set it at 82 and my room increase 10 degrees i wont get a 92 degree, I hope this is understandable.![]()