That was my experience recently. I put one in one of my tanks a few months ago. All he did was sit behind a log and he was aggressive toward all my other catfish. He killed one of my sun cats that I had for over 4 years.
Also, he wouldn't eat anything but live food. I've never encountered a picky catfish, but he wouldn't eat any type of meat, pellets, etc., just live crawfish and worms, and I refuse to feed feeder fish. Not worth it, so I threw him in my backyard pond where he can eat all the minnows he wants.
I'll net him out tomorrow and take a pic for the thread. But yeah, not worth it for an aquarium fish to me.
