The purpose of this research was to get the best treatment addition of Agrobost microorganisms as a reducing agent contamination of sago liquid waste with the addition of microalgae Chlorella sp. This research used a Completely Randomized Design (CRD) with 5 treatments and 3 replications. The treatments in this addition was microalgae Chlorella sp. as much 800 ml/L (6.292.000 cell/ml) of waste …