Article info.

ABSTRACT

Received 09 Jan 2018
Revised 06 Oct 2018

Accepted 30 Nov 2018

This study is to determine the suitable C:N ratio  for growth and survival of spotted scat (Scatophagus argus) cultured in the biofloc system. The experiment was in completely randomized design with three replications of four treatments in different ratios of C:N including (i) control treatment (without adding molasses); (ii) C:N=10:1; (iii) C:N=15:1; (iv) C:N=20:1; each treatment was triplicated. Spotted scat with average initial weight of 3.59 g were stocked in the 0.5 m³ tanks at a density of 40 fish/m³ and cultured at salinity of 5 ppt. Molasses was used to create  and maintain biofloc formation in each treatment. After 4 months of culture, the spotted scat in the C:N=15:1 treatment had an average weight of 34.9 g and had the highest growth, highest survival rate, highest biomass, lower feed conversion ratio, and were significantly different (p<0.05)  from the other treatments. The lowest survival rate and the yield were found out in the control treatment. Thus, the spotted scat cultured in the biofloc system with supplementation of molasses (C:N=15: 1) could be suitable for this species.

Keywords

Biofloc, growth, molasses, C:N ratio, spotted scat

Cited as: Khanh, L.V., Hai, T.N., Phuong, N.T. and Son, V.N., 2018. Effects of different C:N ratios on growth and survival of spotted scat (Scatophagus argus) in the biofloc system. Can Tho University Journal of Science. 54(8): 105-113.