Help maintain a well-balanced aquarium and breakdown excess waste with this easy-to-dose Aqueon PURE Bacteria Supplement! This nitrifying live bacteria converts harmful ammonia and nitrite to less toxic nitrate on surfaces such as filter media， décor and gravel. By using it weekly， the enzymes and bacteria breakdown excess waste from overfeeding or detritus in the aquarium—this can help reduce filter maintenance. Not only does the unique sphere design provide a surface for the bacteria and enzymes to live until conditions are ready to be utilized efficiently， but the unique “time release” design ensures that PURE cannot be overdosed. Plus， any excess bacteria will be waiting until needed. Finally， the spheres virtually disappear when added directly to the aquarium， so you won’t even see them working. They work most effectively in a filtered tank system. Even though PURE doesn’t dissolve entirely， whatever is left behind will go unnoticed and can easily be removed during your next water change. While this does not replace your routine water changes it serves as a safety net in case your underwater buddies’ habitat becomes unbalanced.