Aquarium Pharmaceuticals Ammo-Chips removes deadly ammonia, which adversely affects fish respiration, leading to suffocation and even death. Can be used safely with Phosphate Remover and Super Activated Filter Carbon. Completely rechargeable. Especially recommended for freshwater aquariums and ponds. Directions for Use:Use 1/4 cup (4 tablespoons) of Ammo-Chips for each 10 U.S. gallons of aquarium or pond water. For goldfish aquariums, use 2 tablespoons of rinsed Ammo-Chips for each goldfish. * Rinse thoroughly under tap water to remove any dust caused by shipping vibration. * Place in filter media bag and use in any filtration equipment according to the manufacturer's instructions. To Recharge Ammo-Chips: * Use 1/4 cup (4 tablespoons) of aquarium salt in 1/2 U.S. gallon of water for every 12 oz (340 g) of Ammo-Chips * Soak Ammo-Chips in salt solutions for 2 hours. * Rinse under tap water and re-use. Aquarium Pharmaceuticals Ammo-Chips: 26 oz #79B - Aquarium Filter Chemical Media - Cleanser