Softener FX Advanced Water Softening Resin. 100% Freshwater Softening Resin. Use in Freshwater Aquariums to Remove Unwanted Minerals. Beneficial for Aquatics Plants. Removes Unwanted Minerals. Reduces CO2 Use. Helps Lower pH. Promotes Fish Vitality. Enhances Fish Colors. Essential for Fish Breeding. Regenerable for Repeated Use 6 Times or More. Use in Freshwater Aquariums. Instructions and Guidelines: Best used with fishes from South America, South East Asia, West Africa, Rams, Discus, Apistogramma, Gouramis, Tetras, African Killifish, Angelfish and Corys. Avoid using with Livebearers, Central American Cichlids, Rift Valley Cichlids, Goldfish or Snails. Do not Use With: Tufa Rock, Sea Shells, Bogwood, Coconut Shells or other calcium based substrates. When used as directed 250mL Softener FX will treat 125 US-Gallons or more. Caution: Resin sold moist. Keep closed to prevent drying. Weight varies due to moisture content, product is sold by volume rather than weight. DO NOT LET RESIN DRY OUT!