American Hydro Systems GrassSoGreen Fertilizer # 2655 A nitrogen-rich solution that enhances grass greening. Designed to be fed through the irrigation system and provide a steady stream of a small quantity of nutrient. Will not burn your grass like granular fertilizer. Will not run off and pllute bodies of water. This is the Only fertilizer specifically formulated to be mixed in the same feeder system with Rid O Rust Stain Prevention Formulas. 4- 1 gallon bottles per case