Sorry....before any eggs were put in, when I started it back up after the first hatch, I filled the #1 channel up, because I really wasn't sure how much I needed, putting the humidity way up over 70%. It ran for 2-3 days, gradually dropping to around 51-52% (my boyfriend's preference is around 50% for setting) & I added the eggs at that time. Over time it has varied. I don't log the readings, though that's not a bad idea, actually. One night, before going to bed, it read about 51%, so I let it be--next morning read 35%. Something similar has happened a couple other times. I'm adding only enough water to keep it around 50%. Lately, if it's below 50% @ bedtime (even just at 48-49%), I trickle a little in there & it has been reading usually between 52-54% in the morning. It seems to be settling down, or possibly I'm just managing it better, but I was just trying to find out if what I'm experiencing is considered relatively normal or could there possibly be issues with the incubator. I think the main thing is my monitoring & management & hopefully we can continue to use it for some successful hatching.