RESULTS AND DISCUSSION
There was no significant difference between treatments in measured
water quality variables, either monthly or overall. Overall means±s.e.
for water quality variables were as follows: temperature: 25.6±0.3°C;
dissolved oxygen: 5.8±0.2 mg/L; pH: 8.9±0.1; TAN: 0.90±0.1 mg/L;
un-ionized ammonia-nitrogen: 0.34±0.01 mg/L; total nitrite-nitrogen:
0.05±0.01 mg/L. Over the duration of the study, all water quality samples
for the above parameters represented suitable conditions for prawn
culture (Boyd and Zimmerman 2000).
There was no significant difference (P > 0.05) in average weight between
treatments on any of the sample dates (Figure 1). At harvest,
there were no significant differences (P > 0.05) between treatments in
terms of total yield, average individual weight, FCR, or survival which
averaged 2575 kg/ha, 46 g, 2.3, and 94%, respectively, overall (Table 2).
Initially, it was speculated that larger, faster-growing individuals would