There's always a possibility that it'll work, like duanes mentioned. I haven't had any luck, I had 2 dragonblood peacocks in my 125, I had to end up removing one after he kept the other hiding in the corner.
What do you mean by one of each? My plan was to just move all 3 to a 55 once they grow. The fish that doesn't have a lot of color has a little bit of blue. Does that mean that it is a male?You can get away with multiples of the same male easier in a 72" tank. For all-male in a 48" tank I think one of each works better. Or do a fryeri species tank with 3m:12f. Then the dominant males will have lots of females to distract them.
It makes sense that the colored ones are picking on the non colored one whether the drab fish is male or female.