It’s hard to see what’s going on but it looks like they are moving them back over to the original pit bc of the water change, the mom looks quite nervous, she might even be eating them (I doubt it though) as they keep going back to original pit.Mine have not moved thier kids. But they are the only cichlids in the tank. Like yours the female normally stays with the eggs/fry as dad runs off anything that gets close, be it fish, me, gravelvac....mean little sucker he is......
They have breed like 5 or 6 times now, the fry get to wiggeler stage then disappear overnight. There is a pleco and 4 kuli loaches as well, they may have a hand in fry removal.