Aquaculture is basically fish farming. It is a growing worldwide
industry. There has been a 200% increase in the amount of aquaculture products produced every five years since
1985. Currently 30 million metric tons or about one third of all
seafood product consumed worldwide is produced by aquaculture. The largest producer is
China with about 50% of the total aquaculture production.
Species such as shrimp, tilapia, salmon, crayfish, catfish, trout, carp, mussels, clams, oysters, scallops, and algae's are all farmed. Approximately 98% of all Atlantic salmon currently being consumed comes from aquaculture operations in Canada, Chile, and Norway.
Aquaculture offers the only viable alternative to the continued depletion of the ocean. Unfortunately an aquaculture farm developed with little regard for the environment or neighboring farmers can lead to the destruction of the local environment. This has been a problem in many developing countries where aquaculture is seen as a chance for a better life.
China, Taiwan, Thailand, Ecuador and India have all had aquaculture failures that led to environmental damage, due to unsustainable development or improper management and the loss of millions of dollars. China and Taiwan have yet to fully recover from their aquaculture collapses.
Yet a good aquaculture farm can actually improve the local environment in many areas. The keys are sustainable production levels, every operation is different, and dependent on their resources and location. Sustainable stocking densities, feeds, aeration, pond-based recycling systems, closed recirculating systems, settling ponds, use of wetlands, integration with agriculture, minimal use of fertilizers, and biological filtration can all contribute to a sustainable aquaculture farm. An aquaculture farm can be part a sewage treatment plant, and can actually improve the yield of clean fresh water.
Settling ponds using plants such as duckweed and water hyacinths can reduce high levels of ammonia and phosphorus in water, which can then sustain clams and oysters, algae's such as Gracilaria and fish like tilapia and carp. And after purifying the water for the fish, (or other aquaculture product), the excess plants can then be eaten by the aquaculture product. Incorporating a settling pond, into an aquaculture pond decreases water use, (via recycling), reduces pollution, decreases costs and improves yields.
Duckweed is up to 45% protein, and has high concentrations of the essential amino acids lysine and methionine and is also high in trace minerals and pigments. Fresh duckweed can be fed directly to tilapia. Tilapia is a very fast growing fish and can reach two pounds in six to nine months. It produces a mild, soft, white fish fillet, with a slightly sweet taste. It is lean, tender, and reminds me of flounder or sole. Tilapia are vegetarian and thus can be co grown with shrimp.