Pure Aqua, Inc. designs and manufactures water treatment systems in addition to surface water reverse osmosis systems. In March 2010, Pure Aqua successfully supplied a surface water reverse osmosis system to a major company in Mexico. This surface water reverse osmosis system had a capacity of about 150 GPM from a surface water feed of approximately 250 GPM. The complete surface water reverse osmosis system included chlorination injection, sand filter, activated carbon filter, antiscalant dosing and nanofiltration membranes. The product is expected to have a TDS of 100 ppm. For more information click here: http://www.pureaqua.com/nanofiltration-systems.html