Notes

Aquaponics /ˈækwəˈpɒnᵻks/, refers to any system that combines conventional aquaculture (raising aquatic animals such as snails, fish, crayfish or prawns in tanks) with hydroponics (cultivating plants in water) in a symbiotic environment. In normal aquaculture, excretions from the animals being raised can accumulate in the water, increasing toxicity. In an aquaponic system, water from an aquaculture system is fed to a hydroponic system where the by-products are broken down by Nitrifying bacteria initially into nitrites and subsequently into nitrates , which are utilized by the plants as nutrients, and the water is then recirculated back to the aquaculture system.

As existing hydroponic and aquaculture farming techniques form the basis for all aquaponics systems, the size, complexity, and types of foods grown in an aquaponics system can vary as much as any system found in either distinct farming discipline

HISTORY

Further information: Historical hydroculture

Woodcut from the 13th century Chinese agricultural manual Wang Zhen's Book on Farming (王禎農書) showing rice grown in a floating raft planter system in a pond
Aquaponics has ancient roots, although there is some debate on its first occurrence:

Aztec cultivated agricultural islands known as chinampas in a system considered by some to be the first form of aquaponics for agricultural use[2][3] where plants were raised on stationary (and sometime movable) islands in lake shallows and waste materials dredged from the Chinampa canals and surrounding cities were used to manually irrigate the plants.[2][4]
South China, Thailand, and Indonesia who cultivated and farmed rice in paddy fields in combination with fish are cited as examples of early aquaponics systems.[5] These polycultural farming systems existed in many Far Eastern countries and raised fish such as the oriental loach (泥鳅, ドジョウ),[6] swamp eel (黄鳝, 田鰻), common carp (鯉魚, コイ) and crucian carp (鯽魚) [7] as well as pond snails (田螺) in the paddies.[8][9]
Floating aquaponics systems on polycultural fish ponds were installed in China in more recent years on a large scale growing rice, wheat and canna lily and other crops,[10] with some installations exceeding 2.5 acres (10,000 m2)


Diagram of the University of the Virgin Islands commercial aquaponics system designed to yield 5 metric tons of Tilapia per year.[12]
The development of modern aquaponics is often attributed to the various works of the New Alchemy Institute and the works of Dr. Mark McMurtry et al. at the North Carolina State University.[13] Inspired by the successes of the New Alchemy Institute, and the reciprocating aquaponics techniques developed by Dr. Mark McMurtry et al., other institutes soon followed suit. Starting in 1997, Dr. James Rakocy and his colleagues at the University of the Virgin Islands researched and developed the use of deep water culture hydroponic grow beds in a large-scale aquaponics system.[12]

The first aquaponics research in Canada was a small system added onto existing aquaculture research at a research station in Lethbridge, Alberta. Canada saw a rise in aquaponics setups throughout the ’90s, predominantly as commercial installations raising high-value crops such as trout and lettuce. A setup based on the deep water system developed at the University of Virgin Islands was built in a greenhouse at Brooks, Alberta where Dr. Nick Savidov and colleagues researched aquaponics from a background of plant science. The team made findings on rapid root growth in aquaponics systems and on closing the solid-waste loop, and found that owing to certain advantages in the system over traditional aquaculture, the system can run well at a low pH level, which is favoured by plants but not fish.