Peacock fry tend to be fairly big so you can feed them NLS Growth, Crushed flakes, or BBS right off the bat.
Keep them seperated from other fishes so they won't get eatin'
Keep the water temperature around lower to mid 80's. (If someone begs to differ then by all means )
Keep water clean. Syphon out the poo twice a week.
Feed 4/5 times a day
And big tank space for maximum growth. (Not too big just yet or else they won't be able to find the food)