Uth provide only a hot spot on where they are attached... If ambient of the room cant be maintained then yes you can use the light but do be aware a heatlight will really kill the humidity in the tank... To counter this if your using a screen topped tank you can cover it in aluminum foil leaving an opening for the light and one over the cold side, this will help trap heat and humidity.. Also to create more humidity you can move the water bowl onto the uth or within the heatlights range .