I weighed the trays of eggs in the incubators this morning and wasn’t happy with the results. They’d both lost twice as much weight as they should have. Investigation of the pump for the first incubator showed that the water tube had sealed itself together, so I replaced that and made sure it was working, raising the humidity inside at the same time to try to limit the weight loss a bit more. The other incubator is more basic, so I just added more water to the trays inside.
I then closed up the vents on each to further raise the humidity. Hopefully that will be sufficient to get things back on track. I’ll check again in two or three days.