This study aimed to compare the effect between two different oxygen supply installations, circulating oxygen-water mixing tank and micro-bubbles oxygen supplier for indoor culture, the former supplied oxygen indirectly to pond A by means of mixing oxygen and water in a tank first then pumped the treated water into the pond, the latter using a oxygen producer to supply oxygen directly to pond B by a micro-bubble pump which was installed in the water and in the center area of pond. Pond A & B, 40 m2 in size respectively, were kept 80 cm of water depth with a stocking density of 100 pcs/ m2, i.e. 4,000 pcs/pond, the observation period was from July 7 to September 4 in 1997. The results are summarized as follows:
1. In the observation period, the water of pond B was kept in green with a stable transparency ranging from 20 cm to 25 cm, the bottom of pond A could be seen with a transparency higher than water depth of 80 cm. Except water transparency , DO, pH, ammonia-N, and nitrite-N of Pond B was higher than those of Pond A.
2. FCR of pond A and B were 2.40 and 2.86 respectively.
3. The unit production of pond A was 0.47 kg/m2 which was higher than that of pond B.
4. The shell color of the entire shrimp of pond B harvested turned to be in black instead of normal blue-yellowish color and the antenna flagellum was also abnormally short. We recognized that the abnormal phenomenon mentioned above was impacted by high transparency companion with dirty pond bottom.
5. In spite of survival rate, the growth trend of pond A and B were almost the same. The relationship between body weight (Y) in g and time elapsed (A and B) in day was Y = 0.0849 A+1.822, R2 =0.9565 for shrimp of pond A, and was Y=0.0921B+1.57, R2 =0.959 for pond B.
6. Survival rate of pond A and pond B were 95% and 64% respectively. The lower survival rate obtained in Pond B was caused by a good quantity of larva shrimp were sucked by the micro-bubble pump in the earlier days of stocking. In the other hand, too high DO sometimes as high as 10-14 ppm may caused stress or "gas-bubble" disease especial for larva shrimp in the earlier period of stocking was also discussed in this paper.Lin, M. N., B. S. Tzeng, C. Y. Yeh and Y. Y. Ting (1998) Comparison of the effect of circulating oxygen-water mixing tank and micro-bubbles oxygen supplier for indoor culture of Penaeus monodon. J. Taiwan Fish. Res., 6(1): 43-53.
Key words: DO, pH, Stocking density, Survival rate, Shell color, Antenna flagellum