OK, soo soo far all my chicks have hatched on the 21 day mark.... not this month.... I have a bunch of eggs and I put them in on 3/2-3/3.... one has hatched the rest have been candled and appear to be alive, but not hatching ready. Im sure you guys know what I mean. what I notice is when a chick is about to hatch you can see air pocket and thats it, mine I can still see a little bit of veins, but not much. SOOOO is this normal and how much longer do I keep them in?