the kok did increase in size but the body never really grow. Was wondering if it won’t really grow bigger due to its being slightly short bodied?If you notice the FH stop growing, stop feeding it and do a 100% water change. Monitor the water parameters to make sure Ammonia 0, No2 0, No3 less than 20, PH to be from 7.5 to 8.5 (Best is around 8).
If you wants them to grow fast, you need to feed them food like bloodworm, shrimp. Feeding just pellet will make them grow very slowly.