Fluval Ammonia Remover is a natural ion-exchange media designed to remove toxic ammonia as water passes over it. Controlling ammonia levels reduces stress on fish. Use this product to provide a healthy environment when setting up a new aquarium or maintaining one that contains a higher than average fish stock. Key Features : *Chemical filter media *Controlling ammonia levels creates a safe environment and reduces stress on fish *Particularly useful when setting up a new aquarium or for those with heavy fish stock *Ideal for use with most canister filters 3 x 180 g (6.3 oz) ammonia remover nylon bags *For freshwater use only