neutrino
I was aiming only for the peaceful Geos, because I'm trying to build a peaceful community tank with fish of varying sizes and I want to make sure that no one is going to get bullied.....or worse....
Works well ime. Each mostly minds their own business. In fact, I've had spawning sevs and spawning red head geos in the same tank and, while the sevs were the more dominant in terms of taking and protecting their preferred spawning site, aggression didn't amount to much beyond the periodic chase away from the sevs territory.
I know some people say they've had mean severums-- I haven't, and I've had a lot of of them. Not saying it can't happen, but it's not my experience with them. When I
have seen severums be aggressive it's been in small tanks. My first rotkeil severum was a wild one I had for years that I bought cheap because it was killing everything they put in the tank with it and they wanted rid of it-- tank was a 29 gal if I remember. Same 'killer' fish was a perfect citizen for me in the 75 and 135 gal tank I kept him in. Knew a guy years ago who thought he'd make big $ breeding rotkeils when they were new and expensive, but he couldn't keep his pairs from fighting or killing each other-- he was a discus breeder and was trying to breed the sevs in 29 gal tanks.
I've also had severums with wild angelfish, growout 1" congo tetras, 1.5" growout guianacara, 1.5" growout geos, 2" queen arabesque plecos, and other similar fish with no problem. So, at least from what I've, seen an overly aggressive severum would be the exception, unless it felt crowded or in too small a tank.