Growth Technology pH Down – Professional pH Reducer for Hydroponics & More (250ml / 1L / 5L). Available in3 sizes : 250ml, 1L, and 5L bottles. Hydroponics & Aeroponics. This high-grade formula contains81% phosphoric acid, making it one of the most efficient ways to correct pH levels inhydroponics, coco, soil, and even aquariums.
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