Nutrafin Cycle Biological Aquarium Supplement, 120 mL immediately establishes safe biological aquarium environment, features new high concentration formula, reduces fish loss and establishes essential conditions in new aquarium set-ups. Regular application helps to competitively exclude establishment of undersirable bacteria in aquariums. Fast acting responsive ammonia and nitrite elimination. Allows immediate introduction of fish. Consistent performance from each container due to bio-floc technology for improved shelf life and product viability. Up to date high quality production processes for pure bacterial consortium free of undersirable species. For fresh and saltwater use.