Sledge Hammer is a unique rinse formula designed to remove fertilizer buildup and encourage water movement through soil and soilless mediums Foxfarms Sledge Hammer helps release surface tension in the soil which will allow for optimum absorption of moisture and nutrition throughout the plants root system. Derived from an extract of the Yucca plant called Saponin, SledgeHammer is organic and can be used for both hydroponic and soil applications.