The addition of media to grow biofilms in the Sequencing Batch Reactor (SBR) process, is an advance technology that aims to improve the performance of the reactor as a waste water treatment. SBR works by utilizing microbes that are suspended in the sludge resulting from the SBR process. With the media being added as a place to grow biofilms, there is a consortium of bacteria suspended with attached bacteria. Anaerobic phase is added to give anaerobic bacteria a chance to develop, thus accelerating the breakdown of organic content in liquid waste. Research methods include the best weight of biofilm growing media, namely coconut fiber and palm fiber. And the best stabilization time, to reduce the organic content of wastewater. The research result obtained N-total removal was 93.21 % and COD removal reached 92.11 %. The identification of the dominant bacteria growing in biofilms and those suspended have the same characteristics. The microorganisms which dominantly grew and were found in the media were micrococcus and bacillus.