NHþ4
–N declined steadily until the termination of treatment in
the sterilized wastewaters (Fig. 3(a)). NHþ4
–N was completely removed
at below 148 mg/L NHþ4
–N, while 90 mg/L of NHþ4
–N was
still left in the SN210 test. Phosphorus in the sterilized wastewaters
was eliminated completely in 11 days (Fig. 3(b)).
The initial DOC was in the range of 33–211 mg/L and continuously
increased in all tests (Fig. 3(c)). The change of DOC in the
sterilized wastewaters showed a different trend to that in the
unsterilized wastewaters, indicating that algae species in this
study could not utilize organic matter. This suggests that the decrease
of DOC in the unsterilized wastewaters was due to the activity
of the bacteria.