Establishes Beneficial Bacteria Speeds Up Nitrogen Cycling Helps Prevent Loss from New Tank Syndrome Activ Betta Bio-Activ Gravel is a natural aquarium substrate packed with beneficial bacteria to help speed up the cycling of your aquarium. This allows for the addition of fish into a set up sooner than using non-active substrate as the bacteria can begin consuming ammonia right away.  Beneficial bacteria are essential to a healthy aquarium and should be present before adding livestock. We recommend testing your water often while using this product to ensure your cycle has successfully been completed. Bag contains 1 lb of substrate. Pour entire contents of bag into aquarium and fill with dechlorinated water.  Color: Black