Low Salinity Application to Improve Biofloc System in Early Grow-Out Stage of White Shrimp (Litopenaeus vannamei)

Abstract

Extreme time for the failure of white shrimp culture often occurs at the beginning of rearing, especially during disease attacks and environmental degradation, where high salinity is also a trigger. This research aimed to examine the robustness of shrimp culture with environmental design at low salinity at the beginning of rearing. Methodology: this study was conducted in two plastic ponds (900 m2), each with a seed stocking density (PL-8) of 250 indv/m2, where treatment A (control/initial salinity 27 ppt), while treatment B (low initial salinity 15 ppt) with rearing for 80 days. According to the results from both regimens, salinity changed from the beginning of stocking until the day of 43(27-28 ppt). There began to be similarities, where the addition of water always used normal seawater (33 ppt) until the end. Vibrio harveyii disease attack in DOC 41 occurred in treatment A (control) which was marked by luminescence light from the water rearing, this was different in treatment B which was clean from the luminescence light of pond water. This is also thought to cause the survival rate of control to be lower. It appears that the survival rate (SR) calculation is different, whereas, in treatment A (control), it is only 86%, while in treatment B is 98%. The average body weight in treatment A averaged 8.19±1,36 g/indv, while treatment B averaged 8.69±1,55 g/indv. The results of the FCR calculation in treatment A (control) was around 1.57, while treatment B was 1.42 with total biomass on A 1.402 kg and for treatment B 1.624 kg. The implementation of a low salinity environmental design at the start of rearing can boost the white shrimp culture biofloc system’s robustness, it can be concluded.