Fluval Peat Granules are the all-natural way to soften aquarium water and achieve the pH levels required for breeding and rearing certain tropical fish. Peat contains humic acid tanning agents and trace elements that are essential for various life processes. Highly concentrated for maximum effectiveness this product is recommended for fish that prefer soft acidic water. To ensure optimal conditions its best to test with Nutrafin pH and KH test kits on a regular basis to verify that desired levels are being maintained. Fluval Peat Granules Features and Benefits: - For freshwater use only - All-natural - Controls manipulates and satisfies the breeding requirements of many softer water lower pH loving ornamental tropical fish - Promotes luxurious live plant growth.