Semantic Drift

I've got 6 mummichogs (Fundulus heteroclitus) in a ten-gallon tank, two males and four females. They're really cute little killifish, with a lot of energy and personality. I assume the questions I have about them are applicable to other killis, too, so any killi experts, feel free to help me.

The males recently developed very bright spawning colors, almost black with bright teal spots, so I figured I might as well try my hand at breeding the little guys. The females are also getting pretty fat and gravid-looking, off a diet of bloodworms, grindal worms, and regular flake food. I rigged a couple of spawning mops with acrylic yarn and binder-clipped them to the tank, so they dangle almost to the bottom. I've seen some breeding behavior (males rubbing against females, trying to lead them to the mops), but no eggs on the mops. I realized however, that I don't especially know what a killifish egg looks like, or how to distinguish them from the regular sand and detritus which accumulates on the mop.

So, some questions: How do you know when a female is fully gravid and ready to lay? What color are they? Do killifish like to lay their eggs near the outside of the mop, or further inside? What is the best procedure for removing the eggs from the mop? I figured I could just wash the mops into a very fine mesh net (I have cloth from a broken breeding box I planned to use), or can I remove them with my fingers? How adhesive are they?

Once I get the eggs out, I've got pretty clear guidelines for rearing the eggs and fry. It's just this one step which is frustrating me.

Thanks for any input you may have, and wish me luck with the baby mummies!