ro plant manufacture productsReverse Osmosis (RO) plant manufacturers produce a broad spectrum of water treatment systems, ranging from small domestic units to large-scale industrial plants. These products are typically categorized by their capacity, which is measured in Litres Per Hour (LPH) or Gallons Per Day (GPD), and their intended application.ro plant manufacture productsReverse Osmosis (RO) plant manufacturers produce a broad spectrum of water treatment systems, ranging from small domestic units to large-scale industrial plants. These products are typically categorized by their capacity, which is measured in Litres Per Hour (LPH) or Gallons Per Day (GPD), and their intended application.