2.3 Analysis methods
The biomass was determined by the gravimetric method after drying. In detail, the cellulose membranes (pore size 0.45 µm, d = 5 cm) were dried overnight at 105 °C and weighted after they were cooled down to the room temperature. Cultures with a certain volume (V) were filtered onto a preweighted membrane (W0) and washed twice with distilled water to remove the residual salts. Then the membrane with biomass was weighted (W1) after drying at 105 °C for 24 h. The dry weight of the biomass was calculated as: DW = (W1-W0)/V, where V is the sampling volume (mL) and W0 and W1 the initial and final membrane weights (mg). CODs, NH4-Ns and TPs of the water samples were measured by HACH DR2800 standard methods. The contents of total carbon, hydrogen and nitrogen in the dried biomass was analyzed by a CHNs Analyzer (Thermo scientific Flash 2000). Sludge volume index (SVI) and media pH were analyzed as per standard methods (APHA, 2005).