Ok, prob a misleading title but I couldn't really think of a better one. I have a 20L with a UTH on one side. Temps and Humidity are perfect, when I leave the light off. Is that ok...to have no light in the tank all day? When I leave the light on the ambient temp climbs to about 90 in no time and the humidity dissapears. I have a clear light for daytime and an blue/purple night light. Either one of them causes the heat to skyrocket. I guess I'm just not sure if light is required durring the day. I leave the shades on the window drawn to let some light into the room, but the tank is quite dark. Also, I have two identical hides on opposite sides with the same orientations...but he stays on the cool side, I'm afraid he's not thermoregulating. Any suggestions?