I am a new leopard gecko owner and i have had him about 3 weeks. love him to death. I have a under tank heater a red light for more warmth, the pet store says that they can't see red so it wont hurt their eyes. He always stays on the warm side and in one of his hides. I have a hide on both sides and a humid box. What do i do? I know its supposed to be around 80 in the tank but my thermometer says 73 how do i get it warmer?