Development and Evaluation of an Automatic Feeder Unit for Intensive Fish Farms

The main aim of the present study is to develop, fabricate and evaluate an automatic feeder for fish feeding. The effect of different feed pellets sizes (1, 2 and 3 mm), air flow rates (15, 20 and 25 m3 min-1) and rotational speeds of screw (200, 350, 500, 650 and 800 rpm) were studied. The automatic feeder productivity, efficiency, specific energy consumption and costs were determined. The results indicated that the productivity on the automatic feeder increased from 133.66 to 157.86, 129.15 to 162.15 and 41.12 to 240.73 kg hr-1, with increasing feed pellets size from 1 to 3 mm, air flow rate increased from 15 to 25 m3 min-1 and rotational speed of screw increased from 200 to 800 rpm, respectively. The efficiency of the automatic feeder increased from 61.95 to 77.48, 61.92 to 79.03 and 58.23 to 77.16%, with increasing feed pellets size from 1 to 3 mm, air flow rate increased from 15 to 25 m3 min-1 and rotational speed of screw increased from 200 to 800 rpm, respectively. The specific energy consumption of automatic feeder decreased from 8.93 to 7.25, 10.96 to 5.76 and 10.17 to 6.51 W.hr kg-1, with increasing feed pellets size from 1 to 3 mm, air flow rate increased from 15 to 25 m3 min-1 and rotational speed of screw increased from 2000 to 800 rpm, respectively. The total cost of automatic feeder ranged from 0.05 to 0.29 LE kg-1 for all treatments under study.