So I am trying to hatch a bunch of eggs myself. Last month (Jan/Feb) my friend tried to hatch eggs (remember the Marans that out of a 12 - only one hatched) and only one hatched. So I thought I'd try again myself. I am on Day 10. I candled yesterday. Some were "clear". My brother said those weren't fertile. Several were really "dark" about half way. Some had veins. My question is the one about the "dark" half way. You can't see through it at all. What does this mean?