What are Aquaponics?

Aquaponics combines aquaculture – the raising of aquatic animals like fish – and hydroponics, growing plants in water. In an aquaponics system, the water from a tank containing fish is pumped out and up into the roots of growing plants above, supplying them with all the nutrients they need to thrive. The plants in turn extract the nutrients, clean up the water, and then return it to the fish tank in a seamless symbiotic relationship.

What are Hydroponics?

In a hydroponic growing system, dirt isn’t necessary. Instead, the plants’ roots are fed a nutrient-rich solution while growing in water or some other soilless medium. Alternative inert mediums used in hydroponics are perlite and gravel.

Hydroponics vs. Aquaponics: Which System Works Best?

Both systems work well. Each system holds certain advantages over traditional gardening, as both are relatively low-maintenance, produce a healthy harvest, and are indoors, meaning you can garden in any weather. Which method will work best for you, however, is relative to your specific growing situation.

For a small home garden, choosing between hydroponic or aquaponic gardening is about space and preference. For commercial growers, however, studies have shown aquaponics to be a superior system over its hydroponics cousin in both production and lessened environmental impact.

One study by Doctor Nick Savidov, an Alberta Agriculture, Food, and Rural Development researcher at the Crop Diversification Centre South in Brooks, and Dr. James Rakocy, a leading authority in freshwater aquaponics science and technology from the Agriculture Experiment Station at the University of Virgin Islands, compared greenhouse production of plants under both aquaponics and inorganic hydroponics regimes.

Their initial report concluded that hydroponics actually held an edge in greenhouse production of food plants over aquaponics, but only to a point. However, their second report, which was presented at the 2004 International Conference and Exhibition for Soilless Culture in Singapore, included an updated bar chart that showed it took about six months for the aquaponics microbiology to fully kick in and change fish waste into plant food.

Once that transubstantiation occurred, aquaponics made a quantum leap over inorganic hydroponics in plant production. Their conclusion showed faster-maturing plants with a heavier harvest. The stunning results of the comparison drew skepticism from hydro supporters and surprised even Savidov, a 20-year researcher in inorganic hydroponics. For verification, Savidov double-checked the nutrients and the data used to conduct the study, and the results held true.

Additionally, studies conducted by other Canadian researchers have shown that growing greenhouse plants in cold-climate regions using aquaponics was convincingly superior to growing them hydroponically with an inorganic fertilizer dissolved in water.

Aquaponics proved not only the better growing method, but it offered residual economic benefits as well. Two income streams, one from the fish and one from the vegetables, is a major boost for smaller growers. Also, feeding fish is more economical than buying costly plant nutrients.

Speaking of plant nutrients, there is the issue in hydroponics of eventually having to dispose of nutrient-filled wastewater, which contains polluting nitrates and phosphates.

In an ever more environmentally conscious society, government agencies and environmental regulations are making it more difficult to dump wastewater. This could prove to be a pricey expenditure for commercial hydroponic growers as costs for such disposal will most certainly only rise.

See: The Economics of Hydroponics for a price breakdown of operating a hydroponics system.

Who Wins?

While not everyone agrees, aquaponics seems to have the overall edge. In this system, plants grow faster and with better crop yield. It also produces fish that provide an additional revenue stream. Plus, it’s cheaper to feed the fish than it is to feed the plants.

There is a reduced negative impact on the environment, as aquaponics produces no nutrient-salt-filled wastewater and it saves water due to its recirculatory nature.

Furthermore, many aquaponic gardeners report that root rot, a nasty little parasite and the bane of hydro growers everywhere, is next to non-existent with an aquaponics system. Incidences of disease are reportedly reduced as well.

From a commercial grower’s standpoint, aquaponics makes a strong case over hydroponics. For the home gardener, though, it’s like art: subjective and personal. Your garden is your canvas and you can paint it using whichever method that makes you happiest.

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