For overnight heat (only needed if temps in the tank drop below about 65) I suggest using either a ceramic heat emitter or a heat projector like this: http://www.reptileuv.com/shop/index.php?main_page=product_info&products_id=196. I have mine suspended on adjustable lamp stands so I can fine tune the heat reaching the tank easily. I also use a dimming thermostat to keep the temps within a set range but this isn't necessary if you have everything set at proper heights and check the surface temps around the tank regularly. I also have the Exo Terra 36x18x18. I use a halogen flood light for basking (left side) and a heat projector for nighttime heat (right side). There is a T5 Arcadia UVB light going across the top.