I feed mine a mixture of Hikari massivore, prawns, nightcrawlers from my worm farm, crickets, mealworms and hikari krill when I can get a hold of some. Every fish is different but it is quite possible for a jag to grow an inch a month for the first year. I have even seen these growth rates with a water temperature of 23C degrees as I keep my tanks on the lower range during winter for power saving purposes.