The United States Army employs a mobile, 600 gallon per hour, trailer-mounted, Reverse Osmosis Water Purification Unit (ROWPU) to provide potable water to troops in the field. The ROWPU uses eight, six-inch diameter, spiral wound, thin-film composite membrane elements. The current method used for cleaning these elements is not as effective as desired, and in fact may damage the elements. Continuous replacement of elements is not viable due to the high cost and the need to maintain the ROWPU's mobility. Thus, a more effective chemical cleaner is desired. Following initial chemical component selection, the second phase in the development of an improved cleaning solution involved field testing of newly formulated solutions. Only one solution of five tested, restored product flow; this solution however may have caused damage to the membrane.