Cage culture is a kind of aquaculture. It is made of polyethylene, metal and other materials. At first, the cage culture was mainly in the large water region. The main species were fish. After decades, modern cage culture has improved greatly. The aquaculture has been developed from large water to ponds. Species develop from fish to crabs, monopterus and others. Aquaculture yields and benefits have been greatly improved. That is an important form of modern fisheries.
Cage culture is actually a kind of captivity. The water body inside and outside the net can be naturally flowing. Water is constantly updated through the flow of water, wind, waves and fish. The fresh water outside the box is constantly supplemented. The oxygen and plankton are continuously taken into the net. It can provide the necessary food for the fishes. At the same time, water can also take away the useless fish bait and faeces. It can keep the inside water fresh, which is beneficial to the survivals. Without a doubt, the water exchange can guarantee the oxygen even for density fishery. Also, it can continuously recharge the natural bait. At the same time, it ensures the freshwater quality. It is a modern culture which combines natural environment with intensive cultivation. The cultivation can make full use of the favourable conditions in the large water surface.