Abstract:Brown sugar, Bacillus subtilis, and fermentation solution were added to the indoor intensive culture system of Marsupenaeus japonicus to determine the impacts on water quality, shrimp growth and shrimp survival. The results showed that the flocculation with bio-flocs characteristics, consisting of bacteria, microalgea, protozoa, and amorphous organic detritus, was found under microscope in 14 d in the experimental group. The total amount of inorganic nitrogen in the control group was 56.2 g/m2, while only 4.13 g/m2 in the experimental group. Compared with the control group, the amount of COD and active phosphate increased significantly in the experimental group. The yield of M. japonicus was 0.55 kg/m2 in the control group and 0.65 kg/m2 in the experimental group. The water consumption by 1 kg shrimp production in the control group was 28 t, while only 3.4 t in the experimental group. This study showed that the addition of brown sugar and B. subtilis was effective on water quality control in intensive shrimp culture systems.
