Culture of yellowtail kingfish (Seriola lalandi) in a marine recirculating aquaculture system (RAS) with artificial seawater.

摘要

The development of new species is a high priority for the diversification of the Chilean aquaculture sector. The yellowtail kingfish (Seriola lalandi) is a promising candidate for commercial production in recirculating aquaculture systems (RAS). This paper presents data on the culture of yellowtail kingfish in a marine RAS working for 488 days using artificial sea water. Growth performance, feed conversion, feeding rate, condition factor and mortality were determined for fish having an average initial weight (+or-S.D.) of 0.7+or-0.2 g up to a final average weight of 2006+or-339.0 g. The RAS configuration (drum filter, protein skimmer with ozone, biological nitrification and denitrification, carbon dioxide removal and oxygenation) showed performance stability under the conditions assayed (low water renewal rate). Total ammonia nitrogen and nitrite-nitrogen concentration averaged 0.74+or-0.42 mg/L and 0.21+or-0.24 mg/L respectively. After installation, the denitrification reactor kept nitrate-nitrogen concentrations below 40 mg/L. Nitrate-nitrogen was totally reduced at oxidation reduction potential values between -150 and -250 mV. Water temperature averaged 22.6+or-1.4 degrees C and oxygen was maintained close to saturation levels. Carbon dioxide concentration was in average 8.3+or-2.47 mg/L and pH 7.5+or-0.1. Water renewal rate was 0.45% of the total system volume per day. The system proved the capability to maintain optimal water quality and secured animal welfare.