Thanks for the hints.
I am thinking that I am going to have to get a dedicated hatcher...since I am sure the high humidity spikes have done bad things...my first set hatched much better and more vigorously than this set #3, which would point to a non-nutritional something.
However, I do think I should make sure I change things nutritionally for the next breeding season.
I don't like the idea of adding stuff to the water, since I then need to perfectly clean out waterers. I also don't want to ferment feed, again...more work.
I think I might be able to find calf manna here (not sure...maybe in the next town over), and that would be easy to put on their feed, and I think I will add the brewers yeast to the calf manna.
But, should I start feeding that one month before I start to keep eggs for hatching?
I think I could feed them brewers yeast year 'round, but the calf manna might give them too much protein and kill off my drake, if I feed it non stop.