Most of my hatches have been fridge eggs, since I don't have an adult rooster. My first fridge egg I had I had a rooster that other roosters killed. I pulled some eggs (3) out of the fridge to replace him. I put them in one of those tiny terrible bubble incubators that only fit 3 eggs. 3 hatched. I thought I had all roosters but the smallest egg I set (silky) was a female.