Method of reducing fouling in filters for industrial water system analytical devices

In a method of analyzing the water of an industrial water system wherein an analytical device is used to measure some parameter capable of being measured in the water of said industrial water system, wherein a filter is present in the piping of said industrial water system, and wherein said filter is located either prior to the inlet pipe or in the inlet pipe of said analytical device, the improvement comprising using a water movement device that is capable of moving a sample of water through said filter into the sample chamber of said analytical device and is also capable of moving the same sample of water back out of said analytical device in a manner such that the filters present in the piping of said industrial water system is back flushed out every time the water movement device moves a sample of water in and out of said analytical device.