API Root Tabs Freshwater Aquarium Plant Fertilizer promotes strong roots. Without proper fertilization, aquarium plants gradually yellow, drop their leaves and die. Aquarium plants require essential nutrients for vibrant growth. API Root Tabs are formulated to supply key nutrients, including iron and potassium and carbon, to help new aquatic plants get off to a vigorous start and to keep established plants flourishing. These nutrients are consumed over time in the aquarium and must be replenished for plants to thrive. Add tablets monthly to ensure best results. Contains one (1) API ROOT TABS Freshwater Aquarium Plant Fertilizer 13-Gram 10-Count Box Promotes strong root development for lush plants in freshwater aquariums Contains essential nutrients including iron, potassium and carbon Helps new aquatic plants get off to a vigorous start and to keep established plants flourishing Add tablets to gravel bed every month to ensure best results