I have a quick question about candling. I have not hatched more than a dozen eggs at a time and did not have a problem candling them quickly. I am getting ready to put 48 eggs in the incubator. It will take me a while to candle each one of them. How long can I leave the top off the incubator without causing problems? What if I don't candle them? I know I run the risk of one blowing up and ruining the whole batch if I don't candle. What should I do?