The Effect of Biofloc Technology on Nursery System of Litopenaeus vannamei
The cassava residue was selected as carbon source to study the effect of biofloc technique (BFT) on water quality control, growth performance and seedling emergence in a 40 L culture water of litopenaeus vannamei nursery culture system. The BFA groups included Graded level of C/N (15/1, 20/1 and 25/1) with three parallel samples, compared to the control groups. At the end of the feeding trial 15 days, 10.7%, 14.4% and 46.8% significantly decreased in NH4+-N concentration of the graded level of C/N (p<0.05); 80.2%, 96.0% and 96.2% distinctly decreased in NO2--N concentration (p<0.05); 81.4%, 57.8%, 151% obviously increased on seedling emergence (p<0.05) and 52.2%, 80.8%, 18.2% obviously increased on body weight (p<0.05). The present study elucidates that in the nursery system adding cassava residue as carbon source the culture water quality was evidently improved and heterotrophic bacterium, phytoplankton and zooplankton was also effectively obviously promoted.