Phosphorus is one of several elements that are vitally important for maintaining a vigorous level of growth in a planted aquarium. Dymax Phosphorus Plus is a vital biological element for the growth of aquatic plants. Stunted growth is a sign of a phosphorus deficiency. The ideal phosphorus level will vary from 0.15-1.0mg/L. Phosphorus Plus as directed will enhance and accelerate the growth of aquatic plants without enhancing algae growth. Directions: add 10ml (1 capful) of solution to every 60L of water. Raises phosphorus level by 2mg/L per dose. Dissolve with some water before adding directly into the aquarium. Add 2-3 times per week or as needed in response to signs of phosphorus deficiency. Symptoms: Stunted growth or dark green leaf. Shake well before use.