The problem you will run in to is finding that many peacocks that look different. Once you have blue, red, and yellow there's not much else. Similar fish will fight. I would aim for 10-12 fish.
Packing them in like a can of sardines can work for aggression, but you end of with fish hovering in one spot with little room to move and act normal. You'll get a more realistic tank with correct stocking and allowing the fish to move around more natural.