Recirculating aquaculture system with multi-layer drawer culture tanks for juvenile abalone and its effects

In order to improve the culture efficiency of disk abalone, Haliotis discus hannai, the recirculating aquaculture system (RAS) with multi-layer drawer abalone culture tanks (70 cm×40 cm×10 cm per drawer) were designed. The water quality parameters, energy consumption during experiment period, as well as the growth rate and survival of juvenile abalone in different culture densities were monitored. The results showed that the culture density for 150 individuals per drawer in the recirculating systems was appropriate, which was about 6-9 times of the flow-through systems. The temperature, dissolved oxygen, pH value, salinity, NH4+-N and NO2--N were all maintained within acceptable ranges for the normal growth of disk abalone. The total NH4+-N and NO2--N stabilized around 0.023-0.065 mg/L and 0.014-0.041 mg/L, respectively. The power consumption per day for heating was 1.287 kW·h, where the power consumption for heating sea water accounted for 19.62% of the total power consumption (688.88 kW·h). Compared with conventional flow-through system, it was only one-seventh of energy consumption for heating sea water. The study indicates that it is a kind of mode with the characteristics of safe, high efficiency, energy saving and low pollution for RAS with drawer-type culture tank for disk abalone culture. The results can provide references for choosing abalone culture devices.