Iain, I used warm water and took the eggs out quickly. Only one egg sank all the way to the bottom, the others floated at the air sac. Are they suppose to sink all the way to the bottom? I took the temp of my water before I started and had it at 98* F so that it wouldn't be too hot or too cold. Any additional advice is appreciated. Three of my eggs are on day 31 and haven't pipped. They look a lot like psue's picture. The other eggs I tried this with are a week behind the three that haven't pipped and they floated at the air sac and we can see movement in them.