During the experimental period, the ORP of RAS-O3 was main-
tained within the range 300–320 mV. By adjusting the injection of
pure O2, the oxygen saturations of RAS-C and RAS-O3 were main-
tained at about 110% at the outlets of the fish tanks to exclude the
possibility of increased oxygen concentration being caused by the
ozonation of RAS-O3.