I have two blood parrots and put some ghost shrimp in for the Ropefish. They seemed interested in following them around but they didn't even try to eat them. But my two are like three, maybe four, inches.
Mind you they don't go after the couple guppies I have in there either.
I don't think a geophagus would care for a feeder other than maybe brine shrimp.
No idea about the peacock.