Lower fouling for maximum performance. Hydranautics has over two decades of experience in desalination and over 1.7 million cubic meters (461 million gallons per day) of seawater treated by their SWC (seawater composite) membranes. SWC seawater desalination membranes are available in high productivity 8-inch and 4-inch elements, all offering the highest levels of salt rejection and a consistently pure end product. Membrane formulations are designed to accommodate varying levels of seawater salinities worldwide with reliable field-proven performance.