This research was aimed to get the best various additions of Agrobost which symbiotic microalgae Chlorella sp. in accelerating to reduce of pollutants level in palm oil mill effluent using the scale up experiment technology. This research used Completely Randomized Design with 5 treatments and 3 repetition. This research used microalgae (with abundance ± 6,985,000 cfu/ml) and palm oil mill…