I'm a complete chicken 'hacker' and am only recently taking things a little more seriously, but we've incubated tonnes of our own chickens (mutts - mostly RIR/Australorp mix) but we found that we were having very poor hatches with completely matured chicks dying before pipping - sooooooooo we stopped putting water in the incubator - no water at all. I think living in FL we must have adequate humidity. We now have very high hatch rates.
. Ummmmmmm saying all of that, I've just purchased eggs for the very first time and am now PANICKING about a process I've done countless times