The Tetra Wafer Mix is suitable for both the carnivorous & herbivorous fish & crustaceans. The two different type of wafers are especially designed to sink & accommodate the bottom feeders of an aquarium. The Green Wafers are rich in valuable spirulina algae & are suitable for the herbivorous fish. The Brown Wafer are ideal for the carnivorous bottom-feeding fish. Tetra Wafer Mix at a glance: Green wafers: valuable spirulina algae, especially for herbivorous bottom fish Brown wafers: ideal for carnivorous bottom fish Due to firm consistence of wafers, water isn't clouded Wafers hold their shape to correspond to fish's natural eating habits