Fluval Cycle Biological Enhancer, Aquarium Water Treatment, 16.9 Oz., A8351Brand: Fluval Color: White Features: All natural water care creates a safe biological habitat to prevent fish loss by eliminating ammonia and nitrite Infused with a powerful team of beneficial bacteria that immediately inoculates aquarium water Extremely effective when setting up a new aquarium or introducing new fish to an existing one and useful during water changes and filter media changes, when good bacteria is depleted Regular application helps