Salinity tolerance range test on Channa striata (Bloch, 1793) fingerlings: analysis of the effect of salinity differences on growth performance and aquaculture sustainability

Channa striata is an endemic fish species in Indonesian waters with dwindling stocks in the wild due to high market demand, requiring engineering solutions such as environmental engineering with added salinity to improve production in aquaculture. This study was divided into two stages, each stage using C. striata fingerlings measuring 5.6–6.5 cm. The first stage tested the salinity tolerance range by consistently adding 1, 2, 3, and 4‰ salinity every 24 hours using 100 fish/pond with a volume of 250 L/pond and observing the maximum salinity limit based on the cumulative mortality rate. The second stage involved maintaining 10 test fish/aquarium with a volume of 48 L for 45 days. Analysis of salinity tolerance range tests showed the maximum salinity level of C. striata fingerlings was 21‰, and four salinity treatments were selected, which were 3, 6, 9, and 12‰ (based on the results of salinity tolerance range tests) and 0‰ as a control. The 45-day rearing of test fish showed that the 9‰ treatment resulted in better performance in terms of growth rate, feed utilization rate, and aquaculture production quality, which included blood and flesh chemistry, proximate composition, amino acids, and fatty acids, with significant differences (P < 0.001) compared to other treatments. The conclusion of this study was that the highest salinity level tolerated by C. striata fingerlings is 21‰, treatment with a salinity level of 12‰ at a cumulative mortality rate of 56% showed a decrease in growth rate and aquaculture quality compared to treatment with a salinity level of 9‰ at a cumulative mortality rate of 37%, which was the treatment with the best growth rate and aquaculture production performance among the other treatments. Maintaining the test fish for 45 days showed significant differences (P < 0.001) in growth rate, blood chemical levels, proximate composition, amino acids, and fatty acids.