Fish were held at 28 ± 1 C with
a 12:12 h light: dark photoperiod. Water quality was monitored
daily and maintained at pH ¼ 6.5 ± 0.5 (adjusted with NaHCO3 as
necessary) and dissolved oxygen > 6.0 mg l1. Ammonium, nitrite
and nitrate levels were monitored weekly (0.08 ± 0.02, 0.15 ± 0.05
and 18.30 ± 3.30 mg l1, respectively) and regular water changes
prevented the accumulation of these compounds as well as preventing
background build-up of probiotics..
Daily feed was adjusted on a weekly basis by batch weighing
following a 24 h starvation period.