Size differences? Peacock fry are a nightmare to raise. The larger ones would try to eat any smaller ones. Grab one, kill it, realise it was too big to consume and then spit it out and try the same thing on another. I had to size sort every 3 days....
well, after added some aquarium salt and rise the temp, my 7 remaining peacock are doing fine and swimming healthy, always seem like they are hungry, i try not to feed them too much