The ideal size is a large egg. Med. to large works fine!Ron, I didn't weigh it. Is there a certain weight that's acceptable to set? This one was pretty little, I was just scared if i set it that the chick wouldn't have room etc. I'm going to keep a close eye on her and maybe set some in a few weeks if they look ok.
I have hatched some shipped eggs that were in the 25G size, Which is called peewee. They did have some problems hatching but still hatched.
If the eggs are 45G I would set them!(Large fowl eggs). The eggs were LF orpingtons.