Aquarium salt is obviously essential to saltwater aquariums, but it has uses in freshwater tanks too. You also need it to hatch brine shrimp if raising for food. (Never add salt to an aquarium with plants, or scaleless fishes). We carry the top brands of aquarium salt for freshwater and saltwater tanks, cichlids, reefs and brackish habitats. Use a hydrometer to monitor salt levels, and don't add salt when replacing evaporated water(salt doesn't evaporate).