Abstract：This article aims to research a recirculating aquaculture system (RAS) in mariculture .Here we designed and made a RAS with ‘juvenile sea cucumber-sponge-macroalgae’ in a lab to investigate grow th of sea cucumber ,seawater quality ,discharge amount of waste seawater and pollutants in RAS and in control group .During the 30 d experiment ,concentrations of NH3-N ,NO2--N ,NO3--N ,PO3 -4 -P ,and TOC in seawater of sea cucumber tank in RAS were almost similar to those in control group .Moreovel ,fresh body weight of sea cucumber at the end of the experiment reached 75 .5 g (control group) and 84 .6 g (RAS) from body weight of 50 .0 g at the beginning of the experiment .The seawater of 2 .23 m3 (control group) and 0 .6 m3 (RAS) was respectively discharged into coastal ecosystem ;correspondingly ,pollutants also was discharged ,but discharge amount of NH3-N ,NO2--N ,NO3--N ,PO3 -4 -P ,and TOC in RCS was 21% , 25% ,24% ,23% and 59% of those in group control .T he findings indicate that RAS is an environmentally friendly technology system for industrialized mariculture .
