Probe goes in the tubs -- the eggs will produce their own heat -- therefore if you are only measuring the incubator air then you risk the temps in the egg boxes getting too high. Always in the tub that is closest to hatching. As well the temps in the incubator will fluctuate more than the temps in the tubs which will send the heat up and down creating a never ending cycle of instability.
Yep - in the tub.![]()