Pond Skimmers come in various forms such as the OASE SwimSkim 25 and SwimSkim 50 which float on the water surface and have their own pump built-in. We suggest checking and cleaning the SwimSkim several times a year and check the pump motor impeller for debris entrapment. Clean the filter sponge regularly and always empty the skimmer basket when full. If the surface skimmer is left crammed full of leaves, this can potentially starve the pump of water and cause this to burn out. The OASE AquaSkim and BioSys Skimmer+ require similar attention to ensure these offer many years of serviceable life. We carry genuine OASE spare filter foams and skimmer baskets in stock should you need to replace these quickly. If you cannot find the skimmer part you need, email or call us and we will order this in for you via OASE Germany.