Management of inorganic nitrogen compounds in a closed aquaculture system during imitation for nursery of Litopenaeus vannamei under brackish condition

Abstract

It was aimed to estimate the efficiency of management of inorganic nitrogen compounds under a closed system condition, via addition of carbon source. For this purpose, an imitation experiment for nursery of Litopeanaeus vannamei postlarvae under a brackish condition was conducted, in two closed systems with a salinity of about 18‰: systems with (CS) and without (control) addition of carbon source (molasses) at a carbon to nitrogen ratio (C:N) of 20:1. The levels of total ammonia nitrogen (TAN, 1.39±0.14 mg L−1), nitrite (0.023±0.003 mg L−1) and nitrate (0.49±0.06 mg L−1) in CS system were significantly lower than those in the control system (6.92±0.60, 0.809±0.050 and 2.39±0.47 mg L−1, P < 0.05). The results indicated that carbon source addition to the closed system imitating nursery of L. vannamei postlarvae under a brackish condition well managed the level of inorganic nitrogen compounds during experiment, making it possible to environment-friendly culture L. vannamei at inland areas under a closed condition.