That overhead light looks pretty intense. Tokay geckos are nocturnal & don't require such a strong overhead source of UVB. In my experience it's better to supplement the diet with appropriate vitamins & minerals than to blast a Tokay with strong lighting. We keep a group of 25 Tokay geckos - mostly leucistics & calicos - and set them all up in Freedom Breeder lizard racks with lots of places to hide (including a deep hide box), cypress mulch substrate, calcium supplementation, an insect-based diet & NO uvb light, and they're growing, thriving, breeding & laying eggs. Ambient temperature in that particular room runs 84-87 degrees with a minimum of 60% relative humidity.

Hope this helps!

K