K5 MBBR Bio Media HDPE Biofilm Carrier for Nitrification K5 MBBR Bio Media | HDPE Biofilm Carrier for WWTP & ETP Nitrification Product Overview This K5 MBBR bio media is a virgin HDPE biofilm carrier filter media engineered for enhanced nitrification in WWTP and ETP plants. Its 800 m²/m³ specific surface area and over 95% void ratio create an ideal habitat for slow-growing nitrifying bacteria, delivering ammonia removal for municipal and industrial plants in Latin America,