Ok, so I'm incubating seven coturnix quail eggs, and it's been about a week. I wanted to check on how they're doing, but I can't because of how thick their shells are! I did watch a video in a person who said if the egg is clear when you shine a flashlight through it, it's infertile. But if it's dark inside, it's fertile. Is this correct? If so, I only have one fertile egg! I've also heard of putting them in warm water but I'm afraid that'll spoil the egg. Is there any way I can check to see which ones are going to hatch?