Earthworm is not meant to be the only thing you feed your fish, and you should instead use it as a nutritious supplement. This is because there isn’t enough vitamins, minerals, amino acids and more for the freshwater is not meant to be the only thing you feed your fish, and you should instead use it as a nutritious supplement. This is to be used as a single source of nutrition, and your fish will be healthier and happier if you provide them with a balanced mix of fish food and Earthworm