Using Chlorella vulgaris and iron oxide nanoparticles in a designed bioreactor for aquaculture effluents purification

[Display omitted] •Microalgae and iron oxide nanoparticles were used for purification of aquaculture effluents by the designed bioreactor.•NH4 (93.67 %), NO3 (92.23 %), NO2 (89.3 %), and PO4 (89.25 %) showed the highest reduction percentage, respectively among measured parameters.•The simultaneous use of microalgae and nanoparticles has the desired performance for purification of produced aquaculture wastewaters. Aquaculture operations produce high volumes of wastewater containing suspended solids and nutrients such as phosphorus and nitrogen. Treatment of water effluent from fish production ponds is essential for sustain environment. So, the present study was conducted to evaluate simultaneous use of microalgae and iron oxide nanoparticles (NPs) to purify aquaculture effluents within a designed bioreactor. For designing experiment, effluent samples were collected from fish farms in Sari, Iran. Iron oxide nanoparticles were prepared from Iranian Nano Pishgaman Company. Chlorella vulgaris was captured from the environment, then purified and cultured in the laboratory. After that, NP and microalgae were transferred to the reactor space. TSS (total suspended solid), TDS (total dissolved solid), BOD (biological oxygen demand), pH (power of hydrogen), EC (electrical conductivity), NO3 (nitrates), NO2 (nitrite), NH4, (ammonium) and PO4 (phosphates) were measured during the experiment period which NH4 (93.67 %), NO3 (92.23 %), NO2 (89.3 %), and PO4 (89.25 %) showed the highest reduction percentage, respectively. Also, significant differences among the calculated parameters (except for pH) were observed during the experiment (P