Studi Penurunan Kadar Cod Dan Tss Pada Limbah Cair Rumah Makan Dengan Teknologi Biofilm Anaerob - Aerob Menggunakan Media Bioring Susunan Random (Studi Kasus : Rumah Makan Bakso Krebo Banyumanik)

Generally, Restaurant waste water contain high concentration organic matter such as Chemical Oxygen Demand (COD) dan Total Suspended Solid (TSS) that can continuosly contaminate the water body if not treated. Biofilms one of the waste water treatment alternative that can reduce the number of pollutant effectively. The reseacrh using anaerobic-aerob combination and using bioring with submerged attached growth treatment. In this research, five variations of the residence time are 5,67 hour (340 minute), 11,33 hour (680 minute), 22,67 hour (1.360 minute), 37,77 hour (2.266 minute), dan 56,67 hour (3400 minute). COD removal by the time variation of 13.69 %, 12.04 %, 34.46 %, 44.09 % and 55.52 % , while the removal for TSS are 36.26 %, 53.61 %, 65.88 % ; 73.86 % and 76.83 % . Therefore it can be said that the longer residence time in the biofilter treatment process , the greater the removal efficiency values that occu