Technaflora's pH Up and pH Down enable the gardener to moderate and maintain optimum pH levels. The pH scale is a measure that describes the relative acidity or alkalinity of a solution or medium. Both pH-balancing aids are manufactured using the highest-quality ingredients: potassium hydroxide to raise pH, and nitric acid to lower pH. While ensuring stringent industry safety standards are met, Technaflora's pH Up and pH Down are potent and effective in small doses.