The reuse of water on the culture of pacific white shrimp, litopenaeus vannamei, in BFT system

The use of the same water over multiple culture cycles in a biofloc technology system can be highly beneficial. This study evaluated the effect of different levels of biofloc-rich water on selected water quality indicators and on the productive performance of Pacific white shrimp, Litopenaeus vannamei, juveniles (3.5g) stocked at 312 juveniles/m³ and cultured under conditions of no water exchange. The study was performed over a 30-d period in an 800-L tank system. A total of four biofloc enrichment levels (25, 50, 75, and 100%) and control (0%) were tested with three replicates each. Significant differences in nitrogen compounds were found between the biofloc-enriched water and the zero-enrichment treatment. No statistically significant differences among the biofloc-enriched treatments were found in survival, final weight (8.25g), and feed conversion ratio (FCR) (1.08). The shrimp raised in clear seawater (i.e., a 0% biofloc enrichment) were significantly smaller (7.37g vs. 8.25g) and showed a higher FCR (1.52 vs. 1.08) than the shrimp cultured in the biofloc-rich water. Nevertheless, no differences in yields were found between treatments. The results of this study suggest that culture in biofloc-enriched water produces higher levels of water quality and shrimp performance than culture in natural seawater.