My eggs are about a week old now and the few I have candled show veins, heart beat, and movement. One of them was just a large air bubble (not enough humitity mayby?) And I through it out. I want to candle them all to get the bad ones out but I lose heat rapidly while the top is cracked and I am afraid to open it longer than what it takes to pull an egg out and candle it then open it again to put it back. I close the lid after grabbing the egg but opening and closing it drops the heat level if I do it to often. I have 30 eggs in each hovabator should I do a few each day or am I better off just leaving them alone and seeing what hatches? They are mixed eggs and alot of them are brown shells that I can't see through, will they be ok if I leave them or should I smell test them? This is my first time incubating and every morning the anticipation of candeling an egg to see how they are doing is what motivates me to get out of bed at 4:00 am but I haven't done more than 2 eggs at a time out of fear of losing heat.