Condition pH DO (mg L-1) mg TDS L-1 Duration of phases (anoxic/aerated) Feeding times/Total cycle time Feeding volume /Total volume treated per cycle A1 8.0 -9.0 0.5 to 2.5 45 to 55 1h 56’/1h 56’ B3h 52’/8 h 6.5 L/4.3 L 2 8.0 -9.0 0.0 to 1.3 45 to 55 2h 06’/1h 46’ B4h 12’/8 h 6.5 L/4.3 L 3 8.0 -9.0 0.0 to 2.0 45 to 55 2h 22’/1h 30’ B4h 44’/8 h 6.5 L/4.3 L 4 7.5 0.0 to 2.0 30 to 40 2h 22’/1h 30’ B4h 44’/8 h 6.5 L/4.3 L AShock loading lasted for one day (three 8-hour cycles), and the concentration of 45 to 55 mg TDS L-1 was maintained in the cycles subsequent to this condition BCorresponds to the duration of the two anoxic phases, since feeding was intermittent (only during the nonaerated phases)

Table 1: Description of the operating conditions applied to the FBSBR.