Aquaponics

Aquaponics _{[Back to Top]}

_{July 2nd, 2009}

What is Aquaponics?

Aquaponics, simply described, is the integration of Aquaculture and Horticulture into a single co-dependent system. Aquaculture, in its rudimentary form is fish farming, or the farming of other freshwater/saltwater organisms. In the case of Aquaponics typically freshwater fish are used, except in the rare instances where a particular plant/crop thrives in saltwater(i.e. seaweed). Horticulture is essentially the, "...Science of plant Cultivation."^[1] When referring to aquaponics, the term horticulture is typically used as opposed to the use of the broad term of farming/gardening because Horticulture emphasizes the science of plant growth by improving crop yield, quality, etc.

Aquaponics dates back to ancient civilizations and has seen many improvements since its inception. Modern Aquaponics has close roots to and can be easily misidentified as hydroponics, a cultivation method of growing plants using nutrient enriched solutions without the use of soil. Both Aquaponic and Hydroponic systems can be grown outdoors or indoors (with the use of artificial lighting). The main defining difference between the two systems is the nutrient source. Hydroponic nutrients is made from a specific blend of nutrients, whereas the Aquaponic system uses fish waste to enrich its water.

How does Aquaponics work?

Aquaponics is based on the co-Dependent relationship between the plants and fish within the system. The fish waste produces Ammonia, which is then consumed by microorganisms in the grow bed that convert the ammonia to Nitrites and then Nitrates. The Nitrates are used for growth by the plants which simultaneously 'cleanses' the water, filtering and removing the ammonia - providing clean livable water for the fish.

^{[2] Image Courtesy of Aquaponics Pty. Ltd.}

There are two distinct aquaponic systems;

1) "Deep Water" or "Raft Culture" aquaponics which is the primarily research carried out at the University of the Virgin Islands under the guidance of Dr. James Rakocy ^[3] and;

2) Reciprocating aquaponics ("Ebb and Flow" or "Flood and Drain") based on the techniques developed by Mark McMurtry, et al. at NCSU (such as that implemented by Tom and Paula Speraneo of S&S Aquafarms in West Plains, Missouri.^[4])

Advantages^[5]

The unique advantages of aquaponic systems are:

Conservation through constant water reuse and recycling.
Organic fertilization of plants with natural fish emulsion.
The elimination of solid waste disposal from intensive aquaculture.
The reduction of needed cropland to produce like crops.
The overall reduction of environmental footprint for crop production.
Small efficient commercial installations can be built close to markets therefore reducing food miles.

Disadvantages^[5]

Some conceivable disadvantages with aquaponics are:

Initial expense for housing, tank, plumbing, pump/s, and grow beds.
The infinite number of ways in which a system can be configured lends itself to equally varying results, conflicting research, and successes or failures.
Some Aquaponic installations rely heavily on man-made energy, technology solutions, and environmental control to achieve recirculation and water/ambient temperatures but a system designed with energy conservation in mind (such as utilizing solar heating and the exploitation of gravity to reduce pumping) can be extremely energy efficient.
Whilst careful design can minimize the risk, Aquaponics systems can have multiple 'single points of failure' where problems such as an electrical failure or pipe blockage can lead to a complete loss of fish stock.
Like all aquaculture based systems, stock feed usually consists of fish meal derived from lower value species. Ongoing depletion of wild fish stocks makes this practice unsustainable. There are now, however, organic fish feeds available which may prove to be a viable alternative and negate this concern.

References

^{1. ^ Wikipedia.org Horticulture 30 June 2009 02:11

2.
^ www.aquaponics.com.au Aquaponics Pty. Ltd. 2006

3.
^ Aquaculture - Aquaponic Systems University of the Virgin Islands 2006

4.
^ http://www.jaggartech.com/snsaqua/ S&S Aqua Farm Bioponics System 1997

5. ^Wikipedia.org Aquaponics 26 June 2009 09:23

6. ^ www.fastonline.org Aquaponics 27 January 2008}