Each root tab contains 11 essential nutrients to boost aquatic plant growth. Slow nutrient release will feed your tank for about 2-3 months. Tank conditions such as the type of plants, plant density, temperature, C02 supplementation, frequency of water changes and lighting will affect plant growth and the rate of nutrient absorption, so you may need to place tabs more or less frequently. 

My osmocote Plus root tabs are tank safe for all your inhabitants including fish, shrimp and snails!

Please let me know if you have any questions!