Bacter Vital (Marine) is the modern solution to fully cycle a new aquarium and to energize and recycle established aquariums. Ideal for undergravel filters, natural, planted systems and biofilters. Contains all natural biological catalysts with almost 600 species of microorganisms. Properly cycles the aquariums by synchronizing the sulfur, phosphorous, and carbon cycles with the nitrogen cycle as per modern scientific findings. Neutralizes ammonia, nitrites, and binds heavy metals. Be used with ammonium chloride. One ounce cycles 100 gallons. Available in a 4 oz size.