I'm trying to make a homemade incubator,but I can't keep my temperature stable! It keeps sky rocketing into the 100's!! Does the lightbulb have to be a certain height above the eggs? Or is my lightbulb too hot? I have a 15 watt bulb in a 7 by 5 inch plastic cooler with a sheet of glass on top. Is the cooler too small? I also have the bowl of water and sponge,and of course the thermometer,which i have set right next to the eggs. I'd be grateful for any advice,please! Yes,this is my first time hatching and I know I'm not doing it the "right" way,but the eggs were kind of a surprise that I accepted. And now I'm afraid I'm going to fry them! The eggs are only a few days old,if that helps any.