somewhere on BYC is a series of candling photos with explanations of what is being seen. Maybe if you put "Candling photos," in the search box it will come up. The thing to watch for is any egg with a crack that is oozing - not the usual pip when a chick first tries to hatch. These are en route to being STINK EGGS. If you find one carefully slip it into a plastic bag , seal it tightly and get it away from everything. When they explode they contaminate everything, and then of course you got the STINK.
