Pet fish kept in aquariums feed on both plant and animal matter. Live food and processed food are two categories of food that captive fish are capable of consuming. Live diets include living creatures as well as plants. In contrast, processed diets are man made foods.
Live foods include feeder fish, insects, worms and living plants within an aquarium environment. Processed flake, granule and pellet diets, which provide both animal and plant proteins, are also commonly fed to pet fish. In order to provide a complete and balanced diet to captive fish, most aquarium enthusiasts feed their pet fish a combination of live food and processed food.