Ok so I have just recently made my home made bator out of a styrofoam cooler - 22 qrt. - I chose to opt. Out on the thermastat seeing as I have absolutly no idea how to do it and don't feel like burning anything down. I have put multipul vent holes in the cooler toi help keep the temp at a normal temp. And I am using a 29 watt halogen bulb. I was thinking since it takes me sprayin the inside of the bator down every 30 - 45 mins that I may need to lower the wattage of my bulb, over night I leave the lid cracked and when I checked the temp this morning it was at 86 degrees. I don't want to fry my chickies. ( Don't worry they're not set in their yet!)