封闭循环水养殖哲罗鱼试验

在水温15~17℃下,将5 000尾平均体质量(10±3)g的哲罗鱼Hucho Taimen幼鱼饲养在由24个直径1 800mm×高1 000mm养殖池组成的封闭循环水系统中,以探索工厂化循环水养殖哲罗鱼的主要技术参数。经过8个月的养殖表明:养殖密度达到31.8kg/m~3,成活率96%,肥满度为1.01~1.30,鱼的平均体质量增加350g,体长增加21.3cm,鱼体生长状况良好。生物滤器两天反冲洗一次,有效提高了生物滤器的氨氮转化效率;紫外线消毒方式有效对系统进行了消毒杀菌;监测表明,系统水处理效果显著,其中NH_4~-平均浓度维持在(0.56±0.05)mg/L;NO_2~-含量为(0.15±0.05)mg/L;NO_3~-平均浓度为(41.86±2.62)mg/L;溶解氧为8.37~9.45mg/L;p H8.21~8.63。

Culture Trial of Hucho Taimen in an Industrial Recirculating Water System

Juvenile Taimen with body weight of (10± 3) g was reared in a closed-recirculating water system consisting of 24 tanks of each 1 800 mm in diameter × 1 000 mm in height at water temperature of 15～17℃ for about 8 months to explore the main technical parameters of Hucho Taimen culture in the industrial recirculating aquaculture system.Results showed that the juveniles Taimen had good growth in the industrial recirculating aquaculture system at stocking density of up to 31.8 kg/m3,with survival rate of 96％,condition factor of 1.01～1.30,and increase in average body weight by 350 g and in body length by 21.26 cm.The findings that the bio-filter backwash once every another day increases removal efficiency of ammonia;the ultraviolet ray sterilizes closed-recirculating water system effectively.The monitoring revealed that the system showed significant good effect of water treatment,including maintain of NH4-level at average (1.09± 0.55) mg/L,NO2-(0.15± 0.05) mg/L,NO3-(41.86± 2.62) mg/L,DO 8.37～9.45 mg/L,and pH 8.21～8.63.