I do 35-50% humidity the first 18 days, but it rarely gets up to 50%, mostly 35-40%. Then, anytime on Day 18, I raise that up to 65-70%, but if it slips down closer to 60%, I don't worry too much about it. When they start pipping, they add their own humidity to the air.
I did candle the D'Anvers and the D'Anver/Cochin crosses. Removed one of each, one with blood ring and one that appeared to be infertile for some reason. I will be candling the BRs and others formally later in the week end, maybe even next week, though I did grab a couple of the Delawares and the BR/EE crosses and they are developing okay. I really don't like to candle when I have this many eggs in the bator, but I am paranoid about one seeping or something, though none are shipped.