Effects of biofilter substrate ratios on water quality and growth performance of white leg shrimp (Litopenaeus vannamei) in integrated recirculating aquaculture system

Abstract

This study was carried out to evaluate the growth performance of white leg shrimp and water quality in the RAS integrated multitrophic aquaculture system with different ratios of biofilter substrate. The experiment was conducted in a recirculating system with stocking density of white leg shrimp at 300 shrimp /m3, tilapia at 3 fish / m3 and seaweed at 0.5 kg/ m3 and 3 different biofilter substrates volumes as the experimental treatment (90 L/tank, 60 L/tank and 30 L/tank). Water salinity was at 15‰. Each treatment consisted of 6 composite tanks (2 m3/tank), in which 3 shrimp culture tanks, 1 tilapia tank, 1 seaweed tank and 1 biofilter substrate tank. Shrimp with initial BW (0.37 ± 0.07g) and BL (3.78 ± 0.30 cm) were used for stocking. During the culture, water quality parameters were regular checked and shown within the optimal ranges for the growth of white leg shrimp, tilapia and seaweed. After 84 days of culture,shrimp reached to 15.08 – 16.77 g of body weight, 75.37 –83.29% of survival rate, whereby FCR ranged from 1.51 to 1.54 and shrimp yield ranged from 3.77 to 3.85 kg/m3. There was no significant difference in water quality parameters and shrimp yield among the treatments. This indicated the great potential for the systems for further application, and that with this kind of the integrated multitrophic RAS, 30L of biofilter substrate is good enough to control environment and gave good shrimp performance.