From the water purifier housing Unscrew the filter, with gauze or a scouring pad can be cleaned (no need to use other cleaning agents) when brushing to expose the new surface can be. When the filter constantly scrub thinning, thin to a certain extent, please replace the filter. In this case, there are two simple criteria to help you decide: A. visual observation, very fine filter to reduce the diameter of about 1/2 of the original. B. The use of a longer time than usual normal cleaning cycle, the water becomes small.