they grow not too fast but not too slow....so an average of an 1" a month...but don't expect any large size growth in these guys....some go with the 1" growth and some just goes slower like 1/2" a month
Mine grew about 8 or 9 inches in the first 6 months, then about another 6 inches in the next 6 months, then finally slowed down and is now over 24 inches after about 2.5 years. He started at about 3 or 4 inches.
What is being fed to the fish? my fish is about 4-6 inches and giving it feeders every other night. Treid to get them off feeders with carnivore sinking pellets floating pellets, flakes,no success.