I know it says "peaceful"... but I found mine was the opposite. (Although, admittedly, he seemed to be maturing much faster than my other cichlids.) He chased and nipped at all of my other cichlids (even the ones much bigger than he was, including a flametail that he killed with in a few days of getting him). Finally, I got tired of it and sold him back to my LFS. I don't know if I just got a mutent or if they are more agressive than people let on, but this was my experience. My LFS owner said they are "hit or miss" on their agression and the ones who matured faster tended to be the bigger jerks. Luck of the draw I guess.