農業部-水產試驗所全球資訊網農業部-水產試驗所全球資訊網

本試驗以1.8頓FRP桶進行吳郭魚零換水養殖試驗，在0、10與20 psu三種鹽度下，成長隨鹽度增加而明顯降低，活存則只在20 psu明顯降低。在10、20與30尾/m2三種密度下，有無放置收集袋，活存均在98.3%以上，成長則均隨密度增加而降低，不過密度20與密度10相差不顯著，產量則分別增加80-90%、每公斤用水量則分別節省44-48%。換水、掛網、收集袋都能減緩水中硝酸及懸浮固體的累積及促進吳郭魚成長，掛網、收集袋還具有維持pH的效果。其中去除氨氮及懸浮顆粒的效果以收集袋最佳，不過平均日增重與產量則以掛網組最佳，分別為3.35±0.23g與12.7±0.8 kg/m3。每公斤吳郭魚用水量也以掛網組最低為79±5公升，較換水組節省72％。以上結果顯示：零換水吳郭魚養殖，相較於一般傳統換水養殖，不但成長與換肉率沒有降低，活存率提高至100%，單位產量還增加了4倍左右，用水量更降低了98%。

This study used 1.8 tons FRP tank to culture tilapia under zero water exchange condition. In the salinity of 0,10, 20 psu, growth reduced as salinity increased, while survival only decreased in 20 psu. In the density of 10. 20. 30/m2, with bag or not, survival rates were more than 98.3% in all groups, but growth decreased as density increased. The difference in growth was small between density of 10 and 20, therefore, the yields were 80-90% higher in 20/m2 compare to that of 10/m2 with water saving of 44-48%. Water exchange, bag and mat can remove solid and nitrate in the water column and promote growth of tilapia. Bag and mat can further stabilize pH. While bag had best ability in removing solid and nitrate, mat had best growth of 3.35±0.23 g and yield of 12.7±0.8 kg/m3. In mat group, to produce one kg of tilapia, least water of 79±5 liter was used, which saved 72% compared to exchange group. By comparison with traditional tilapia culture, under zero water exchange condition, survival rate of tilapia can reach to 100%, yield can increase more than 4 times and save water for more than 98% without decrease in growth and FCR.