I'm debating on relying these thermometers I just bought or wait on that one to get here.
If you are referring to the one posted from Incubator ware-house---they are not all accurate either. I got about 6 of them---they pretty much read different---for sure the humidity. If you had it set at 37.5(99.5) and it was reading 92 why not adjust it higher? Or you thought the 37.5 was accurate? From your hatch you were probably off by close 2 degree's. "I" would use the same as what I used last time but bump the temp up 1 1/2 degree's F(38.3c). I would then see what happen---see if your chicks hatch closer to true day 21. If you get any other thermometer you will have to use it a whole hatch to see how close it is unless you get a high dollar guaranteed accurate one. I go by my eggs hatching to determine how accurate a thermostat is or how I need to adjust.
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