My Xingu I pikes roped me in. I purchased them at about 3in. They took krill from my hands, and allowed me to pet them. About 2 years later, they were up to 12". They also ate everything, frozen foods, pelletes, algae wafers, freeze-dried krill, earthworms, you name it. They were good tank mates (granted the other fish wnere't mout-sized). They left my other fish alone, and kept my dominant Red Devil at bay. It was also interesting to watch them puzzle through how to get food that was trapped in floating plants. I now have two tanks dedicated to Crenicichla Compressiceps (55-gal planted w/4, and 130-gallon with another 4). Just as much personality, lighter bio-load.