Thanks fo the comments.
This morning the mother is VERY aggressive. She's hitting everyone hard who gets too close. I can almost hear the impacts. She's even attacking the dominant male, and winning. What an amazing fish! Most of the eggs look like they're still there.
I figured out why both parents were pulling sand out from underneath the rock they spawned on: that is where they are going to take the fry when they hatch. Pretty smart, huh? They were planning things and I had no idea they were so organized.