* * EXCELLENT SOIL CONDITIONER: for improving potting mixes and adding better drainage in containers. | - PREMIUM ACTIVATED CARBON: A highly active granular activated carbon (GAC) manufactured from selected grades of bituminous coal and designed for use in aquarium applications. CHADA AQUA KEY works best in all FILTER, FINE MESH FILTER MEDIA BAGS, similar bag, rectors, canister filters, in-tank filters, etc. | - SUPERIOR ADSORPTION PROPERTIES: remove dyes, tannins, odor, medicinal residuals, and toxic organics from aquarium water. Which rapidly adsorbs dissolved pollutants from water, including yellow-brown tint, toxins, chlorine, most medications, some heavy metal. | - HIGH-QUALITY CARBON: provides an excellent surface area, meso-pore structure, high density, and superior hardness, removes foul odors from aquarium water, LEAVING A CRISP CLEAN SMELL. | - EASY TO USE: Use 1/2 cup per 50 gallons; Change every 2-4 weeks; Rinse with deionized water or water is taken from the aquarium before use. One bag contains 27.5 lbs, our 6x10 highly -active granular activated carbon for use in all aquariums, tanks, and ponds.