dissolved oxygen concentration, pH and temperature
were checked daily. Water salinity was adjusted with
dechlorinated tap water or 37% SW when needed.
Water temperature, pH and dissolved oxygen were
29 ± 1, 7.8 ± 0.02 and 6.2 ± 0.06 mg l-1 (mean
value of all treatment groups ± SE), respectively.
The fish were exposed to a 12-h light-dark photoperiod
using overhead fluorescent lights. There were no
mortalities during the experiment.