HM SeriesCharles Austen HM Series Water Pump The HM series of water pumps come with multiple benefits for both the aquatic and hydroponic market. Suitable for both submersible or external use the HM series can uses its high pressure pumping system to move large amounts of water. Comes with a filter sock to help remove algae, debris and keep the water clean. Quiet and reliable when in operation. High performance with increased head pressure