Ok so hubby got the Hova-Bator 1602N with turner and a fan for me. The bator is here but still wating on the fan (I should have gotten the mail yesterday. Its here). I have it pluged in so I can get the thermostat set. How much of a temp variation will there be when I get the fan installed? I need slightly longer screws than what came with it. I guess my other questions are about the other items you mentioned. The tube and sponge. Fill me in please. Will your method work with the Hova-Bator also? I want to get my first test hatch going. lol If anyone else wants to give their info that would be great.