The objective of this work was to investigate the efficiency of both double drain and screen filter on solids removal in recirculating aquaculture system to improve the water quality and increase the fish growth rate. A model was developed to determine the solids removal in recirculating aquaculture system. By fitting the predictions of the model to measured settleable and suspended solids, settleabe solids removal was determined that about 0.0304 to 0.0556 kg m-3 (30.40 to 55.60 mg l-1) while it was 0.039 kg m-3 (39 mg l-1) for the theoretical approach and suspended solids removal was determined that about 0.0123 to 0.0806 kg m-3 (12.30 to 80.60 mg l-1) while it was from 0.0124 to 0.1425 kg m-3 for the theoretical approach. It was calculated that the hydrocyclone and drum filter efficiency to remove the solids from the system ranged from 27.4 to 57.79 % and15.46 to 57.71 % respectively. It was calculated that the hydrocyclone and drum filter efficiency to remove the solids from the system ranged from 27.4 to 57.79 % and15.46 to 57.71 % respectively. The daily average of settleable and suspended solids removed by hydrocyclone and drum filter ranged from 0.33 to 6.26 kg/day and 0.11 to 11.43 kg/day, respectively. The model results were in a reasonable agreement with the experimental ones. |