Application of three microbiological preparations to control of water quality in industrialized shrimp culture

The experiment was conducted to determine the supplement of microbiological preparations ［Bacillus licheniformis （BL）, Rhodopseudomonas capsulate（RC）, Lactobacillus spp.（LB）］ on ammonia-N, nitrite-N, nitrate-N, chemical oxygen demand and active phosphate in industrialized shrimp culture. The experiments was composed of two teams and every team had two frequencies：control group，BL+RC added once per 7 days （G1）, BL+RC added once per 3 days （G2）, LB+BL added once per 7 days （G3） and LB+BL added once per 3 days （G4）. The results showed that different microbiological preparations had different preponderance. At the aspect of reducing NH4+, compared with control group, G1, G2 and G3 reduced 62%, 63% and 65%, respectively.In the first 21 days, G2 reduced 79% compared with control group. As for NO2-, compared with comparison, G1 reduced 46%. The best effect for controlling water quality was group G1. In addition, no groups resulted in significantly reducedPO43- and COD. There is no striking difference between two frequencies in controlling the water quality. With the culture time increasing each index trended to increase.