HAILEA HX-4500 2000lph Adjustable Pump M/Head 2.8m With Air Pipe This versatile little pump has fully adjustable low rate regulators and have the ability to work in low water conditions. The HX-4500 also comes with the added bonus of an oxygen mixing unit as standard. ABS case and high quality stainless steel shaft which is suitable for fresh and sea water and ideal for use with nutrient salts. It has a built in flow regulator to control flow easily and ideal for pumping nutrients in NFT/Flood anf Drain applications. This pump is mounted on suction cups for secure location and is designed for continuous use. The mixing accessory which comes with HX-4500 model allows large quantities of air to be mixed with the water while the pump is in use considerably increasing the concentration of oxygen (O2).