I candle at one week(brown shell) and eliminate all infertile eggs since they don't count. I also don't want to keep infertile eggs at optimum bacteria growth temperatures for 3 weeks. I bought a Little Giant incubator for $35 from
Tractor Supply and figured I'd save a little money from hatching my own as well as have some fun. The thing works well enough, but I modified the incubator before even starting eggs in it. First thing was to add in a small 120v fan on a light dimmer switch.
First hatch was 20 out of 24, so 83%. After that first hatch, it seemed obvious more incubator modification was needed. There were still relative hot and cold spots, the water troughs didn't dry evenly, and the holes in the bottom leaked water if I spilled any water accidentally when filling the troughs. I added a baffle to the fan, siliconed the holes in the bottom shut, blocked some of the top holes that seemed responsible for drafts and humidity swings, added aluminum tape behind the heater elements and around some of the windows for better heat reflection, and marked the temperature control dial.
Next hatch was 44 out of 48, so 92%. Not bad for a highly modified incubator. The water troughs evaporated evenly this time, and the humidity and temperature were as even and good as can be expected in such a small volume incubator. No more modifications since I can't find any faults with the incubator.
Next hatch was 13 out of 14, or 93%. Hope this helps show what can be done to improve hatch rates. I only turned the eggs twice a day, but I turn 180 degrees each time. I mark the eggs on opposite sides with two different marks and just turn them morning and evening. Other than that, I've never had an egg pip that didn't fully hatch. So far, none of the chicks have died or had issues. I think this home hatching delivers a superior chick compared to what we can mail order.
. And definitely better than any incubator I've tried!
