I feed my P. dolloi that's about 12" long daily. I feed it as much as it can eat in the span of a few minutes, and I make sure to not leave any food in the aquarium after feeding time in order to prevent the water from fouling. It enjoys eating beef heart, fish fillets, algae wafers, shrimp pellets, Hikari Tropical Sinking Wafers, and Hikari Tropical Food Sticks; I alternate which food that I feed between each feeding.