these elements were not added to the growth media. The culture
was kept in these conditions for 40 cycles. The third test was
performed to keep selected the mixed culture resulting from the
second test, using the FCW2 as substrate. In the third test, depending
on the chemical composition of the substrate utilized, the
C/N/P mmole ratio and OLR were of 100/19.7/3.9 and of
38 ± 2 mmole C L1 d1, respectively. In this case, also, the minerals
needed for cell growth were already present in the FCW2, and
the final nitrogen and phosphorus concentration in the reactor
(N = 52.4 mg L1 and P = 23 mg L1) were greater than those of
the first test but lower than the values considered to limit PHA
storage (Reddy and Mohan, 2012). The culture was kept in these
conditions for 31 cycles.