RowaPhos was developed in Germany for treating main water supplies. RowaPhos is a patented, man made ferric hydroxide material chemically engineered for the efficient removal of phosphates, arsenic and silicates from fresh and saltwater. 100 g/100 mL RowaPhos will remove 3ppm of phosphate from 100 US gallons of saltwater.250 g/250 mL RowaPhos ..