In the aquaculture fish farming model, the fish wastes accumulate in the water which increases the toxicity for the fish. This water is then transferred to a hydroponic system where the by-products, or effluent from the aquaculture tanks are filtered out of the water as nutrition for the plants, which cleans the water and then it is returned back to the fish tanks for the animals. Aquaponics is a portmanteau of both the terms aquaculture and hydroponic.
The history of aquaponics was utilized in China and Thailand where they farmed and cultivated rice paddies in a combination with fish. The Aztecs also were reported to have used cultivated agricultural islands which are known as chinampas and are considered by some researchers to be the first form of aquaponics for agricultural uses.
In more recent times, and in the Western world, aquaponics was researched at the New Alchemy Institute in Cape Cod experimented from 1969 to 1991 with the use of bioshelters and wastewater management via crop production. In Israel, researchers Tim Evans, Kyle Petrie and Chris Somerville, all Irish nationals, are working to create ways for poor families in arid regions to secure their own food supplies with rooftop aquaponics.
In a recently developed urban model, Sweet Water Organics, which is partnered along with the Sweet Water Foundation, which focuses on inter-generational and interdisciplinary educational programming for sustainability with primary focus on the potentials of urban agriculture and aquaculture in the 21st century. Sweet Water Organics converted an old dilapidated, abandoned crane factory in Milwaukee, WI. and converted it into an indoor wetland using aquaponics which raises approximately 80,000 fish in tanks which are topped by beds of lettuce along with other crops. The mission at Sweet Water Organics is simple, which is to provide fresh, safe food for the local community while maintaining reasonable pricing and respecting the environment.
They began the upgrade of the facility in 2008, which was inspired by Will Allen’s three tiered, bio-intensive, simulated wetlands. In this form of a re-circulating system, the fish waste acts as a natural fertilizer for the plant growth and the plants become the water filter. Vegetation is not limited to lettuce, and also includes basil, watercress, tomatoes, peppers, chard, sprouts (broccoli, radish and sunflower), pea shoots and spinach. Fish that are also raised there are tilapia and lake perch, for which the numbers have been decreasing in numbers in Lake Michigan since the 1990’s due to invasive species like the zebra and quagga mussels. The number of lake perch in the Wisconsin waters of Lake Michigan declined from 24.6 million in 1990 to 2.6 million in 2000, and down to 316,219 in 2009. Wisconsin closed the commercial perch fishery on Lake Michigan in 1996 along with Illinois and Indiana in 1996 due to the rapid decline in perch numbers, however, Michigan still allows some tribal harvests of the perch. Read the following for more information on ethical safe fish to eat.
Milwaukee is striving to become the latest recipient of the Stockholm Water Prize, with the new Graduate School of Freshwater Science at the University of Wisconsin-Milwaukee, which will be led by Australian David Garman, a water technology scientist and entrepreneur. This new addition to the school will be folded into the existing University of Wisconsin-Milwaukee’s Great Lakes Water Institute, which has already had discussions with people in Singapore, according to Val Klump, a senior scientist at the existing Institute. The school already is working on projects involved in urban agriculture and urban aquaculture, primarily aquaculture fish farming with aquaponic systems that also grow produce. Milwaukee is striving to become a leader in the new climate of sustainable water use. The future is looking bright for the use of aquaponics in aquaculture fish farming in Milwaukee, and the rest of the world as well as research and needs advance.