No you don't need to drop the ambient temps over night. They usually do anyway on their own. There is a difference between surface temps and mbient temps heat pds basically only control surface temps lamps with effect both. You need to provide a warm spot (around 90º) cool spot (around 80º) and ambient air temps between 77-83 (max low of 75 and high of 86º) if you need day and night lamps to do this use them if you don't need lamps you don't need to. The answer will be found in your temps.