Kinetic growth rate analysis of Coelastrella sp. in aquaculture wastewater.

The demand for sustainable food and energy production continues to rapidly rise. Utilizing aquaculture wastewater as microalgae growth medium is a potential opportunity for nutrient recycling and industrial symbiosis, but more research is required to understand how best to design and scale-up a dual-purpose facility. This study investigates the growth of Coelastrella sp. in aquaculture wastewater compared to industry-standard growth medium BG-11 and modified tap water as controls. Though cell size and pigment density varied throughout media, aquaculture wastewater performed very comparably to BG-11 as a microalgae culture broth. The Monod equation can model Coelastrella sp. growth based on absorbance and phosphorus data with at least 93% accuracy once lag phase data is excluded. Though nutrient remediation was very effective, the recovered biomass lipid fraction was relatively low compared to other Coelastrella species and particularly low compared to other algal species. Conceptually, there is evidence to support this implementation of industrial symbiosis, but various technical challenges still need to be addressed.