การทดลองใช้จุลินทรีย์สำเร็จรูปในเชิงพาณิชย์เพื่อควบคุมคุณภาพน้ำในการเลี้ยงกุ้งกุลาดำระบบปิด / ธนิกา จินตนะพันธ์ = Experimental use of commercial microbial products for controlling water qualities in the black tiger shrimp closed system ponds / Thanika Chintanaphan
A study was conducted to compare the efficacy of different microbial products in controlling the water quality in shrimp culture ponds. Four 1-rai grow-out ponds were stocked with 50,000 twenty days postlarvae. Closed circulating system was designed for this experiment. Commercial mixture bacteria was added to two treatment ponds every week. The other two ponds were used as the control. Water quality and biological parameters were monitored throughout the 120 days grow-out period. These included ammonium-N, nitrite-N, nitrate-N, orthophosphate, sediment accumulation, growth rate, size of shrimp, shrimp production, survival and the profit after harvest. Ammonium-N and nitrite-N of the treatment and control were not significantly different (p>0.05) with in the culture period. Nitrate-N and orthophosphate of the treatment ponds were significantly higher than the control (p<0.05) in the third and the fourth month. Dissolved oxygen, pH and water salinity were not significantly different (p>0.05) between the treatment and control. The sediment accumulation in the treatment ponds were less than in the control. Growth rate of shrimp of the treatment and control were not significantly different (p>0.05), but the treatment group had better marketable size shrimp. Survival and total yield of the treatment group was also higher than the control, leading to the higher profit from the treatment ponds.
