Mala's are hogs my - 12" eats 3-4 silverslides daily - I've seen him eat a 2x 5" Cichlids that were badly injured by other cichlids. He used to eat shrimp but lost the taste for it. A secure lid is essential - they try to escape the tank by using their heads as battering rams. Grew him from 3-4" to 12" in less than a year in a 55gal.- moved him to a 120XH -48x24x24 - to much room - he hit that glass lid like a ballistic missle. He's now in a 75 with 4 bricks on the lid. Used to use duct tape - not any more. He doesn't need tankmates - one of the most impressive fish I've ever owned.