Your setup is amazing on many levels! For one you've created an environment that allows multiple species of pseudopimelodids to co-exist, probably due to each being able to have their own territory and that you have managed to have a community collection of fish that seemingly eat the same foods as well. Many of the fish you have are often difficult to wean off live feeder fish, obviously it can be done, nice. For years, at least half of my hobby has been dedicated to pseudopimelodids so I really admire your collection. Perhaps the most difficult thing in keeping cephalosilirus species such as apurensis and fowleri is their aggression and territorial nature, yours seem to get along nicely. My c. fowleri would tolerate other catfish species to a degree, nipping fins, etc. but would kill any other pseudopimelodid introduced to the tank. I raised a c. apurensis to 20" and sold it a couple of years ago as it outgrew my tank, kept it alone based on their reputation. (It's now around 28" in her second home.) Your experience seems different, so far. I don't recall seeing the size of your tank but in general terms a larger tank seems to reduce aggression in these species as does keeping them well fed! Excellent….