Oh sorry I didn't answer that he does have a uva/uvb tube style bulb in his enclosure is the one producing the whitish light.I know Tom has already asked you this but can't see an answer, so apologies if I've mssed it, but you mention a CHE but do you have a source of UVB - such as a tube fitting or a mercury vapour bulb (MVB)?
The mvb gives heat light and essential uvb in one bulb.
UVB helps them digest their food and absorb the calcium etc.