°Â²¹³Ù±ð°ù±·°¿³æâ„¢An advanced nitrogen removal filter designed to service smaller flows with less maintenance and energy consumption than standard submerged filters with backwashing. °Â²¹³Ù±ð°ù±·°¿³æâ„¢ LSThe WaterNOx-LSâ„¢ is an advanced nitrogen removal add-on for the thorough denitrification of nitrified effluent in residential and commercial applications. The WaterNOx-LSâ„¢ uses a mixture of agricultural sulphur and limestone in a submerged up-flow configuration to remove nitrogen via a passive autotrophic process.