5 Year Member
I think they are sifting out the micro-worms. I think some of the larger Geophagine Cichlids (Satanoperca daemon?) eat small food items.I noticed my adult Apistogramma sifting sand where micro worms have accumulated. Do you think the worms are still too small to be used this way? I wonder if a significant amount of worms would be consumed by the sifting activity.