2.2. Environmental conditions
Environmental conditions in both the fish farm and control site
were monitored at the beginning and end of this study. Water temperature
(WT), salinity (SAL), dissolved oxygen (DO) and pH were
monitored at 1 m water depth using a YSI 6920 probe (YSI, Yellow
Springs, Ohio, USA). Meanwhile, triplicate water samples were collected
for inorganic nutrient determination at the same depth.
Inorganic nutrient concentrations (NO3–N, NO2–N, NH4–N and
PO4–P) in water samples were measured according to the method
of Grasshoff et al. (1983).