so you have the CHE heating up the bottom of your tank like a hotplate on a dimmer switch, sounds like trouble. Personally since I have mine in a 4feet by 3 feet enclosure I have the flexwatt for the bellyheat and I Have a infrared heat bulb on a rheostat to heat the ambient temperature as I cannot for the life of me get the room where he is hot enough without costing me a fortune in the winter.
http://www.exo-terra.com/download/hi...rared_100W.jpg
Its like that but i get it at the home improvement place where they sell bulbs Its like a 220watt for your size with the dimmer.
and for humidity I just mist and provide a moist hide during shedding time, right now the humidity is about 65 though.