He's a senegal bichir. approximately 4 years old. He's in a 55 gallon tank with 3 other fish: another sengal bichir ( same age), a leaf fish and a cory catfish. I change the water last month and do it monthly with a 75 % water change out. I havent put any new fish or decorations in the tank for over a year. I feel him carnivore pellets and frozen shrimp blocks