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The aim of the study was to evaluate the performance of Litopenaeus vannamei in an intensive photo-heterotrophic hypersaline system with minimal seawater replacement, and establish relationships between parameters of a stochastic production model and relevant water quality variables. Six experimental 1000m(2) lined ponds were stocked at a density of 120shrimpm(-2) for a 105-day trial. Salinity increased from 37 to 45 +/- 2g/L, and the water level was maintained with the weekly addition of filtered seawater, equivalent to 1.6% per day. The stochastic model predicted that, at harvest, there is 95% confidence that the system produces between 12.1 and 14.7t/ha with a mean final individual weight of 13.1g and a mean survival of 84.2%. Sensitivity analyses showed that dissolved oxygen and individual final weight of shrimp were the main variables influencing yield variance. Nitrogenous compounds were maintained between optimal cultivation levels (NH3-NH4+=0.73 +/- 0.43mg/L, N-NO2-=0.09 +/- 0.05mg/L, N-NO3-=3.22 +/- 0.11mg/L). Heterotrophic bacteria (6.6 +/- 3.4x10(5)CFU/ml) and chlorophyll- concentration (108.5 +/- 80.2g/L) showed a similar development pattern, indicating a strong relationship between bacteria and microalgae during cultivation. Vibrio spp.concentrations were low (1.24 +/- 1.42x10(3)CFU/ml). It was shown that thephoto-heterotrophic system could be used in hypersaline conditions, typical ofsemi-arid regions, to consistently produce between 12.1 and 14.7t/ha in 15weeks.