I have two thermometers in my incubator. I had 4 and the two that were the closest together in readings I used. I have a Little Giant with a factory installed fan. I also have a humidity guage. The humidity guage and thermometer 1 set fit into the egg holds. The second thermometer sits on top of the eggs and is a regular style thermometer with the glass and red stuff. I set up the incubator Wed morning and got it dialed in at 99.5 with the thermometers sitting on the egg turner tray. It stayed that way until Fri when I got my eggs. I let them sit for about 12 hourse and put them in the incubator. I knew that the temp would lower by putting the eggs in but the next morning the top thermometer (laying on top of the eggs) is lower temp than the one that it as mid egg level. Is this because of the reduced airflow through the eggs? Is this something to worry about with a fan circulated incubator? Or should I change the temp? The thermometer at egg level is as close to 99.5 as I can tell, and the one on top of the eggs is about 98.5 or so perhaps a tad lower. Should I just let it ride like that or do something about it?