I've put quite a few more small eggs in them, hand turned them, and had them hatch fine. I do keep them out of the very corners, the hatch rate was similar to when there were fewer hand turned eggs. These were home eggs, not shipped.
Thank you for responding!!!
I am doing a project with a school. We will have 5 + incubators running, 3 different brands. Also, many different kinds of eggs. I know we will be getting many banty eggs and I want to have enough space for everything. How many extra do you think I can add roughly?
I know I have had over 60 banty eggs in there with no problem. Somebody who also uses that brand once said that they have put over 80 small bantam eggs in. So I guess it is pretty much what you can fit in. I do not like putting them in the very corners or squashed up along the edges because I think the airflow is too limited, I also watch the vent holes on the sides. When I turn them I also try to move the ones from the side to the middle and just actually pick one egg up and just turn the rest.