Table 1 BOD₅ (mg/L) in effluent filtered through sand, gravel and charcoal medium at different incubation periods.

0 h

24 h

48 h

72 h

24 h

48 h

72 h

24 h

48 h

72 h

AFC

2467 ± 2.89^d

1200 ± 5.77^c

972 ± 4.04^c

875 ± 4.62^d

1405 ± 2.89^b

1104 ± 2.31^b

910 ± 5.77^b

1000 ± 5.77^b

610 ± 2.89^c

393 ± 2.31^d

LMC

3466 ± 3.46^b

1271 ± 1.73^b

1126 ± 1.73^b

895 ± 2.31^c

993 ± 1.73^d

718 ± 4.04^d

670 ± 4.04^d

983 ± 2.89^c

800 ± 5.20^b

620 ± 1.73^b

OIR

3077 ± 4.04^c

1041 ± 1.15^d

983 ± 3.46^c

936 ± 2.31^b

1120 ± 2.31^c

998 ± 1.15^c

841 ± 4.62^c

873 ± 5.20^d

805 ± 2.31^b

595 ± 2.31^c

IIO

3631 ± 2.89^a

1341 ± 4.04^a

1169 ± 6.35^a

1031 ± 4.04^a

1770 ± 5.20^a

1399 ± 2.89^a

1178 ± 7.51^a

1640 ± 4.04^a

1014 ± 5.47^a

825 ± 4.04^a