Nutrient substrate for beautiful and permanent plant growth in all freshwater aquariums. Works for 5 years guaranteed. Nutrient store: contains important plant nutrients, such as iron. Clay components store nutrients and release them again, as required. Efficiently prevents unwanted algae growth by promoting plant growth. How to use for the initial setup: add the nutrient substrate and cover with a layer of rinsed substrate. Package contents: 1 pack of ready to use, long-lasting nutrient substrate.