You are killing me I think,this is enough I don't like heavily stocking my tanks would I have to be worried Bout territory issues
between catfish? I never had a catfish actually DO anything....I mean I had a 2 huge Pardalis that would chase my Jags and JDs and stuff, but they never cared about the other 7 or so catfish that they shared with......eclipse, brown hoplo, Raphael, synodontis, CAEs, Channel. Even at 2 feet the Channel didn't bother anything, even the 2-3" convicts that he could swallow. Raised him on pellets, therefore he never saw other fish as a food source, as crazy as it sounds. I worry about cichlid aggression, even then it's only to an extent. Just be a keen observer and learn to read behaviors and you will be fine. When I do catfish, I do them by the lots, if I could get ANY species to pair-up and breed, it would certainly be a new species, but also and entirely different family I could add to the resume.
I encourage people to keep catfish in groups, especially Synodontis due to they're all hard to sex, and Synos are actually a schooling fish in the wild anyway. I just pretend they are Corys or RTS or other shark-catfish. IME, hoplos actually do quite well in groups, buying only one from the petshop I worked at from a group I observed daily and behave similarly to typical Corys, especially when kept w/ Corys. The other few I mentioned and a few others do the same in the right environment w/ plenty of food and cover.