Aquaculture Production Methods

Aquaculture Production Techniques

Pond Culture

Pond cultures are the most common aquaculture production system. An aquaculture project can consist of only one pond, or hundreds of specially designed ponds. The most common form of aquaculture pond is an earthen pond which is created by earth levees, although other materials can be used. To the right is a cross section of the typical pond. The size of the pond varies depending upon its purpose. Some ponds do not have the water inflow or a drain and are often used for cage culture. A single pond can produce between 2,000 and 10,000 pounds per acre annually depending upon the production in level.

Caged culture

Caged culture involves growing the aquatic organism within cages, the sizes of which may vary depending upon their intended purpose. Unlike pond culture, cages do not require the construction of special pond structures. The cages can be placed in any water source as long as an adequate flow of water is maintained through the cage. Production in cages is comparable to that in ponds per unit area. One drawback of cage farming is that they are susceptible to biological pollution, where the non-native species being cultured escapes and disrupts the local ecosystem. To the right is a diagram of two circular cages. The cage on the right is cross sectioned.

Raceway culture

Raceway cultures can also be called tank culture. The tanks can be constructed of cement, fiberglass, or any other durable material. Tank culture is more sophisticated and productive than either pond or cage, but they are also more expensive. This is because the tanks are constructed so that there is a continual flow of water through the system. The continual replenishment of the water flushes out wastes and gives the fish more room to live and grow and limits stress on the fish. The water recirculation can be achieved several ways. The tanks can be set on an incline such that gravity powers the water flow.

Recirculating systems

Recirculating systems are the most expensive means of culturing fish but also the most environmentally friendly. This system is similar to raceway cultures except the water flow is controlled by pumps that return the water to a reservoir where the wastes are extracted. The water is then pumped back into the tanks to be recycled. Production rates in these systems vary.