Introduced in 1991 after approximately two years of research and field testing this product immediately became the standard for aquatic fertilization. Pondtabbs water soluble tablets combine controlled nitrogen release with rapid nutrient availability in a form which provides optimum feeding for all of your aquatic plants. When used as directed this product will not effect algae growth or have any negative effect on fish. It is recommended that you feed your plants monthly during the growing season at a rate of one tablet per gallon of soil. When the water temperature rises above 72 degrees feeding should be increased to every two weeks. Insert the Pondtabbs with your finger deep into the soil three inches from the crown of the plant. When using multiple tablets, space the uniformly around the plant. Nutrients will release within five minutes.