Osmosis is the natural movement of water through a semipermeable membrane to an area of higher solution concentration to reach equilibrium. Reverse osmosis uses pressure to reverse the natural osmotic pressure and separate water from the solute or impurities in it. From a solution of high solute concentration, water gets forced through a semipermeable membrane, producing pure water. There are different kinds of RO membranes for different types of water and pressure levels. We recommend having a water analysis and a water pressure test, so you can choose the best membrane for your application.