I use regular incan house hold bulbs and those deep reflective dome fixtures.
I take my thermometer readings with wired probe on the basking brance, 8
to 10'' from the lamp, and where the little chammie will be.
Incans are getting harder to find at the store, so I buy cases of 24.
I use 25, 40 and 60W.
I summer, need to replace them with a lower watt.