I use a red heat bulb for additional warmth. But if your ambient temps are OK it's not needed at all. They do not have sunlight requirements but day/night cycle (like natural ambient light, indirect. Not bulbs) can be sorta helpful if they won't eat during the day. Fluorescent bulbs can stress them out by being light they can see (as opposed to the red, which they cannot see) making them feel insecure and not hidden. I feed mine in very little light, basically enough for me to see, and my girl eats fine.