Hi, we are trying to hatch our first ever batch of khaki Campbell cross ducks. Today is day 29 though & no sign of any action. I quickly & carefully candled the eggs just now and all the eggs have what seem to be relatively small air sacs, about 1/5 of the egg, is that too small? I thought they should be bigger at this stage? Nothing to be seen or heard that indicate internal pipping, surely that should have happened by now? I've kept temp & humidity to recommended levels & just last week could little moving webbed feet when I candled the eggs. I fear the worst, the kids are going to be so disappointed. Any ideas anyone??