3 pack. API SUPER ACTIVATED CARBON makes your aquarium crystal clear with its premium-grade, high porosity carbon for maximum absorption and minimal aquarium maintenance, removing dissolved organics, colors, toxins, and fish remedies. This product will not raise phosphate levels in your tank, and will not affect pH. It comes in a convenient, easy-to-use pouch and is compatible with freshwater and saltwater aquariums. API SUPER ACTIVATED CARBON removes dissolved particles, as well as odors, colors, toxins, fish remedies, and other dissolved organics that carbon filters may leave behind, which can adversely affect aquarium conditions. Made with a higher grade of carbon, API SUPER ACTIVATED CARBON absorbs more than regular carbon and does not affect pH. API SUPER ACTIVATED CARBON is safe for all aquarium types, even sensitive reef systems. API ACTIVATED FILTER CARBON should be placed in the filter inside the filter cartridge, or in a filter media bag. Be sure to follow your filter manufacturer's instructions.