The research on Membrane Bio-Reactors (MBRs) is being conducted using microalgae-bacteria symbiosis to create a dual-purpose system for wastewater treatment and biomass cultivation. Microalgae can be further processed to create high-value chemicals, animal/human nutrition, biofuels, etc. Microalgae produces the O2 for bacterial respiration while the bacteria respires CO2 required for the algae to photosynthesize hence reducing cost of aeration of MBRs.