Aeration is the oxygen saturation of water in pond. Aeration plays a major role in the culture shrimp culture systems. Animal growth is mainly depending on the aeration level in the pond. To increase dissolved oxygen (DO) level in the pond, there are surface and sub-surface aerators.
Paddle wheel aerators are the most commonly used surface aerators in the aquaculture field to increase the DO level of the pond irrespective of climatic condition. These paddle wheel aerators are switched off at the time of feeding as the distributed feed gets drifted by the water current. If the water current is very strong then the feed tends to accumulate in the centre of the pond before the shrimp consuming the feed. Due to high stocking densities if the farmer fed the pond in late evening with DO level is on the reduction side combined with a cloudy day then it leads to Dissolved oxygen insufficiency in the pond and the animals tend to surface and in some cases severe mortality also can be expected. Though aspirator type aerators are available in the market, the farmers are reluctant to buy to overcome this issue.
To overcome this problem, a gear box to integrate paddle wheel aerator with propeller aspirator is designed. The integration is done by making some changes in the gearbox. Mostly worm gears are used in the gear box of paddle wheel aerators. In that worm shaft is extended to some length below the gearbox and connected to the propeller shaft at the end. The extended worm shaft covered with a Vacuum doom with a provision for atmosphere air to come in.
Advantages of the integration are, generally during feeding the paddle wheel aerators were switched off and aspirators are on so that the DO level in the pond will be maintained in optimum level.