Did this for a while on a small scale... didn't take it as far as I wanted to though. I thought it worked pretty well. Gave me a chance to see a bunch of different apistos in one tank. Noted several things though...
1. tank needs to be *heavily* planted/decorated with a ton of hiding spots. Bullying was an issue... not awful, but could be a problem in the long term if it is not diffused, or the victim cant easily find refuge that he is comfortable with. I'm also wondering if overstocking like in a rift lake males only tank would work?
2. One per species seemed to work best for me... aggression seemed worse between like species/complexes.
3. Apistos are the type of fish where if you find a male you really like, a compulsion to find a female and move them to their own tank to breed *will* develop... or maybe that was just me?
I would be very interested in hearing your experiences if you decide to give it a try. It's something I would definitely consider playing with again in the future.