I have one that is about six/seven inches. He has put on about two inches in four months. So far he has been pretty easy going. I do my normal water changes from the tap and it does not phase him. My filter broke last week and the tank got nasty and he was fine. I also have weaned onto krill and sometimes pellets. He weaned really quickly. My second one was a different story. It was not possible to wean him off of feeders, he grew slower and my endi got him. they are neat fish, but nothing special.