Percs might do well when they are small, but they get big, and very territorial IME. When I plan a tank I plan to keep a tank that can run together for the next 5 to 10 years, not for the next 6 months. IME with perc they did fine when they were very small for a few months and then established there territory and got defensive. One thing if you have a 250g tank, quite a different scenario if your doing a 90g IMO.