I got one of these recently, having not seen them before. Hes in with cichlids but has received a bit of a beating but its nothing new to see a catfish introduced to a cichlid tank and initially get some trouble. It stops after a few days, and i think mines definately tough enough to ride it out.
Long term though these guys get to 12" and can be quite territorial so ive read. They will also eat smaller tankmates once larger. Long term mine will go in my 130gallon, but is currently in a 48G.
Because your catfish is there before the cichlids hes less likely to get a beating in actual fact.
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