The Muck Vac connects to your garden hose and the specially designed vacuum head creates a high pressure suction lift up the vacuum pipe. You can suck up small pebbles and leaves and organic debris from the pond bottom. Some people use it to clean the filter tank out. The waste water is pumped out continuously to the grass or a drain in your garden. It really is quite powerful if your water pressure is good. You will also make a water change at the same time you are cleaning the pond.