Bio-Phos is a form of Phosphorous Acid (H3PO3) - often referred to as phosphonic acid) not to be confused with phosphoric acid (H3PO4) that you are all probably aware of for pH correction. There is much research to show good action against many of the root diseases associated with hydroponic growing eg Phytophthora / Pythium. It is translocated well within the plant and has good effect as a foliar spray against many mildew species also. Tomato, Pepper and Lettuce growers have all reported favorably over its use.
