A pond skimmer provides an essential mechanical filtration for a pond. The skimmer collects surface debris like leaves, needles, excess food, cones and other wind borne objects. By removing this debris from the pond you will reduce the build-up of muck and detruis that can cloud water or make seasonal cleaning a real chore. The pump is often installed in the skimmer to create a suction effect than slowly brings pond water into the skimmer where a basket collects the unwanted materials for easy cleaning. In larger pond multiple skimmers are a good idea as this will prevent unwanted stagnant zones.