This study aims to evaluate the effects of different salinities on the growth and survival rates of mullet (liza subviridis) in oder to contribute to aquaculture development in coastal area of the Mekong delta. The experiment was conducted with 7 treatments of different salinities of 0, 5, 10, 15, 20, 25 and 30 thousandths applying opening system. Hatchery produced fish fingerlings of 0.45 g (one-month old) were stocked at a density of 30 fish per 60-L plastic tank. The fish were fed daily with pellet feed of 35 percent protein. Rearing water were continuously aerated. After 2 months of culture, the fish from salinity of 15 thousandths grew fastest with final body weight of 2.88 g, daily weight gain of 31.9 mg/day and specific growth rate of 1.35 percent/ day, which were significantly different from those in the other treatments (p0.05). The fish exposed to 0 thousandths (11.28 mg/day, 1.01 percent/ngay) and 30 thousandths (17.61 mg/ day, 1.08 percent/ day) had the poorest growth. Feed ratio were ranging from 2.2-6.6, the highest were obtained from the treatment 0 thousandths (6.6). The highest survival rates (91.1 and 90 percent) were obtained from the treatments of 20 and 15 percent0, the poorest survival rate (31.3 percent) was observed in the treatment of 0 thousandths. This study indicated that grey mullet (1 to 3 month old stage) is very euryhaline and the optimum salinity for fish growth and suvival rate is at 15-20 thousandths.
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