I have a school of 5-6 of these guys in my 125g. They are busy swimmers going back and forth the length of the tank around mid-level. The males will "flash" to attract females. Its pretty amazing to see in person. Their coloring shows up best with a dark background and substrate with plenty of lush green growth around them. I feed a diet of frozen bloodworms, live blackworms, flakes and crumble.
I keep a trio in a 29g.1 male, 2 females. He is the boss of the tank, but doesn't bite, just charges around to keep everyone in place. I think he did kill a neon tetra that was fin nipping one of his females. Didn't see it happen, just one day came home and the nipper was killed but not eaten. Beautiful fish and very strong swimmers. in retrospect, I would recommend a clear swimming area atleast 4 ft long with a section of high current at mid level