The mixed-culture microalgae-bacteria consortium was enriched from a domestic wastewater treatment plant in Ulsan, Korea. Diluted anaerobic digestion effluent from a full-scale anaerobic digester was used as a medium for the culture growth. Four sets (S1-S4) of Semi-continuous biogas conditioning systems were operated with synthetic biogas (60% CH4 40% CO2, v/v), in different HRT, and GRT conditions. The possibility of a microalgae-based biogas conditioning system with an anaerobic digestion effluent medium was investigated in this study.