Both MFC and PMFC setups were placed in a climate control cabinet (Microclima 1750 Snijders, Tilburg, the Neth- erlands). In this manner, environmental conditions were fixed at illumination period of 14 hday−1, average light density in the photo active region of 596±161 μmol m−2 s−1, tempera- ture of 25°C and humidity of 75%.