Highly active, coal based carbon is used in research laboratories and universities. Patented activation process creates a high purity, premium grade carbon with optimal pore structure and a large surface area for maximum absorption. Unique design provides fast, continuous and thorough removal of odors, colors, organic pollutants, toxic compounds and medications. The result is a cleaner, healthier aquarium enviroment. Ideal for freshwater, marine and reef aquariums containing sensitive fish, plants, and invertebrates.