Good record keeping.
When you say clears, do you do an eggtopsy to see if there was no development (infertile) or if they failed in the first few days?
I do, I think her roo played favorites/ this is still early in the yr breeding season. I picked them up in Jan. Plus she didn't do any fertility checks or hatch anything recently.
If the controller applies power to the heat element as either on or off rather than incrementally, there will always be big temperature swings. Especially with a near instant read thermometer like the spot check. I adjust so that the thermostat kicks on when near my preferred temperature.
Yes. I was actually quite surprised at how close this thermostat was able to perform given it was meant for home brewing.