In another study, Millamena et al. (1991) also found recirculation systems to be better than flow-through systems in terms of reproductive traits for P. monodon. In another study in Thailand, a recirculation system designed in earthen ponds for rearing postlarval 15 day-old P. monodon for 60 days resulted in an average survival of 56% when practiced at a water exchange of 10% either once or twice a week ( Kaweekietyota et al., 2007). Survival of the shrimp in sand-based recirculation system obtained in the present experiments is much higher than in the recirculation system designed in earthen ponds in Thailand.