Tetra Crystal Water clears cloudy water and suspended particles from the aquarium water fast, safely and reliably.Crystal Water contains selected minerals which remove cloudiness and haziness of all kinds. With its gentle mode of action, Crystal Water it is absolutely harmless for all aquarium inhabitants and quickly provides crystal clear water. The effectiveness of the product becomes visible by a white cloud, which is not dangerous and clears away after a few hours. The active ingredients in Tetra Crystal Water bind small particles in the water into larger ones that can then be filtered from the water by the aquarium filter. For an optimum effect the filter should be cleaned regularly. First effects are visible after 2 to 3 hours; the water is crystal clear within 6 to 12 hours. Tetra Crystal Water is suitable for all freshwater aquariums.