Yes -They get large, 16" in the wild - so tanks 2' in width min., very aggressive even with their own shoal, and they will eat anything - flake, pellet, krill, shrimp, crustaceans, dead and live.
Hmm be good with gar? Not getting them right away got to sell a horse and change the barn into a fish area. Thinking maybe a couple florida gar in a 10'x10'x4' pond?