Phycoremediation in aquaculture; a win-win paradigm

ABSTRACT The ever-growing aquaculture sector has a great economic and environmental cost as it has been responsible for severe water pollution and ecosystems failure. The presence of high concentrations of different pollution factors is a big challenge for the aquaculture industry to sustain fishery production. The conventional wastewater treatment systems demand urgent efforts to avoid secondary pollution. It is high time to develop green technology for aquaculture wastewater treatment and bioremediation could be the major intervention towards this. Phycoremediation, being an energy efficient technique, is employed as a tertiary treatment strategy for nutrient recovery from aquaculture wastewaters. Instead of being wasted, nutrients can be fed to algae to generate biomass for feed, bio-fuel and other valuable products. This review article gives an outlook to the studies that have explained the unique activity of microalgae, macroalgae and algae-bacteria consortia to scavenge nutrients from the aquaculture wastewater. The review also addresses the factors affecting phycoremediation, advantages of phycoremediation as well as the limitations and disadvantages that hamper this technique from full-scale use. Lastly, suggesting sustainability strategies for phycoremediation application in aquaculture will enable the selection of appropriate algae and help development of simple environment-friendly economical and sustainable aquaculture systems adopting bioremediation and parallel production of algae biomass for various purposes. GRAPHICAL ABSTRACT