Effects of different carbon sources on water quality, growth performance and survival of western white shrimp (Litopenaeus vannamei Boone, 1931) in zero-water exchange system

Eeffect of different dietary carbon sources on water quality, growth performance and survival of western white shrimp Litopenaeus vannamei post larvae was investigated in zero-water exchange system. Shrimp postlarvae with mean weight of 98.47±8.60 mg and mean length of 22.39± 1.70 mm were fed for 32 days in fiberglass containers with 130 liters volume of water and density of 1 individual per liter in five treatments including one control with water exchange and four biofloc treatments with adding different carbon sources including molass, starch, wheat flour and mixture of them at equal weight ratios with 15% to 9% of body weight. In the values of water quality parameters including temperature, salinity, dissolved oxygen and pH, no significant differences were observed among the biofloc treatments (P>0.05). Maximum pH (8.27 ± 0.09) and maximum dissolved oxygen (6.37 ± 0.56 mg/lit) was in water exchange treatment. Maximum and minimum level of ammonia was 0.43± 0.34 and 0.09± 0.07 mg/lit in water exchange treatment without floc and biofloc treatment with adding starch of carbon sources, respectively and showed significant difference between treatments (P