Its only day 6 but I decided to try candling one egg to see what I could see. The air pocket seemed bigger than I thought it would be this early, and I could see veins coming down from the air pocket, but I couldn't see anything else. It was a lighter colored Marans egg so I guess that isn't unusual. Now I am nervous about candling any more as I was advised to wait till Day 10 or risk killing the eggs... hm. Maybe I will just rearrange them in the bator tomorrow by type and mark them with numbers so I can keep track of what is what and who is who. I will have to candle a couple though as I've promised the boys they could stay up late to see what is inside the eggs.
You won't kill your eggs by candling them, don't worry. The air pocket and veins are a sign if life, that is a good thing to see.