Our premium laboratory grade super activated carbon captures micro and macro organic particles while removing unwanted odor, spent medication, discoloration and various toxins through absorption. The large surface area on the carbon granules promote colonization of beneficial bacteria essential to a healthy aquatic environment. Safe for both freshwater and marine aquariums. Directions: Pour media into the free media bag and briefly rinse under running tap water prior to use. Media bag may be rinsed periodically to remove excess debris. Replace media regularly according to order load.