If you are using a UTH to provide the hot side temperature I would recommend a 75 watt infrared heat bulb centered on the cage with a dimmer or thermostat to keep the air temperature in the cage around 80 F.
I personally use and recommend these bulbs:
http://www.petsmart.com/product/inde...AvailInUS%2FNo
They can be run 24/7 without any issue and put off very little visible light.