General Hydroponics FloraMicro Hardwater for Plants, 16-Ounce Use FloraMicro Hard water if your tap water is over 200 ppm (or contains Calcium above 70 ppm) Flora Series enhances flavor, nutrition, aroma, potency and essential oils in both hydroponic and soil cultivated plants Flora Blend is very clean product that can be utilized in all hydroponic systems Not sold in IL