candled the eggs this a.m. day 16. 20 out of the 21 that were fertile the first candling are looking good. Almost tossed one, but looked again awhile later and could definitely see nice looking little blood vessels in there, good thing I looked again.
Definitely think my past problem was the humidity to high. Have been letting the incubator go totally dry and the humidity % goes down in the mid 30's or so, and just adding 1 straw of water when it goes dry will shoot it up to 60% or more. Using vents full open and full closed to try and keep a happy medium between 40% and 50% range. Air sacks on the eggs seem to be about right for the 16th day, so keeping my fingers crossed.
My altitude is just about 500 ft above sea level here, so the oxygen content of the air is better than it would be at higher altitudes. There are five 1/8" ventilation holes that come standard drilled into the bottom of the LG incubators and this Farm Innovator one too. And also eight 1/8" ventilation holes on the top of the incubator. When you couple that with a forced air fan, I don't think there is any way possible on this green earth that it would be possible to starve hatching ducklings for air, or cause a carbon dioxide poisoning condition inside the egg, just isn't possible with all those ventilation holes and a forced air fan. Maybe without the forced air fan, but with the forced air fan, i'm putting those 2 red caps in whenever I need to control humidity. Humidity on the high side- out they come! on the lower side and in they both go.
Seems I recall reading somewhere the red capped extra ventilation holes were for hatching at high level altitude's above 6 thousand feet or so where the air is thinner.