Get prepared for the newest members of your finned family with API Quick Start Freshwater And Saltwater Aquarium Nitrifying Bacteria. This solution allows for the immediate addition of fish to a new tank as it starts the natural aquarium cycle with beneficial bacteria. That bacteria converts toxic ammonia into harmless nitrate. It also prevents fish loss in both freshwater and saltwater aquariums. API Quick Start Freshwater And Saltwater Aquarium Nitrifying Bacteria is an ideal option when starting a new aquarium， adding new fish or when changing water and filter.