Aquaponics is Natural by Design
Feb 29, 2012 04:42PM
By Tanner Jones
The soothing sounds of flowing water over rocks, beds of greenery and beautiful orange koi and goldfish are usually associated with Zen gardens, but for Stéphane Herbert-Fort, owner and operator of Tucson-based Local Roots Aquaponics, this is the setting of his highly sustainable, all-natural aquaponics farm.
Herbert-Fort, a former graduate student at the University of Arizona and longtime farmer and research scientist, created Local Roots Aquaponics about a year ago, with the intention of producing food, “sustainably and locally, using the safest and most natural material possible.” By replacing traditional mined fertilizer with lava rock from northern Arizona, reusing food-grade plastics for containment systems and implementing a water recirculation system that drastically reduces the amount of water wasted in desert climates, Herbert-Fort uses a system of farming known as aquaponics, “to produce the purest food, locally.”
Aquaponics is the combination of aquaculture, or raising fish, with hydroponics, the cultivation of plants in water. Aquaponics farms are inclusive, sustainable ecosystems that rely on the natural symbiotic relationship of fish byproducts as plant nutrients, and the root systems of plants as water filtration for the fish. Aquaponics systems vary from single systems that can easily fit in a small yard and cost less than $1,000, to more expensive multi-tiered systems. Each has subsystems that bed the plants and a rearing tank to raise the fish.
The fish can range from those that are edible, such as catfish, tilapia, bluegill and others, to more aesthetic varieties, such as koi or goldfish. In the rearing tank, fish solids, rich in nitrates from waste, uneaten food, detached biofilms and other particulates collect at the bottom of the tank. In traditional aquaculture, these solids collect and increase the pH levels in the water, making it toxic for the fish; however, in an aquaponics
system, these solids create nitrogen-rich water that is directed into the hydroponics subsystems where the plants are grown.
The subsystems replace traditional gardening soil with lava rocks, gravel, clay beads or other types of solid media. The rock bedding creates an anchor for the plants’ root systems, while allowing water to flow freely through the bed, delivering nitrogen-laden water from the fish tank straight to the plants’ root systems. “Since all the nutrients are being brought to the roots, there is no competition for water among the system,”
Herbert-Fort states. “So, instead of plants using energy in competition, that energy goes to growth.”
The lack of competition among plants is what gives aquaponics systems the ability to produce, as many aquaponics farmers suggest, about twice as many plants per square foot as that of traditional farming, and twice as fast. Because the nutrients are so rich and the water flow is constant, the opportunities for growing various species are virtually limitless. In one of Herbert-Fort’s multi-tiered module systems are found a
wide variety of crops, including bananas, strawberries, parsley, dill, onion, cabbage, radish, cauliflower, spinach, chamomile, beets, mint and lettuce.
As the water flows through the roots of the subsystems, the water is naturally filtered. That clean water is pumped back into the fish tank, oxygenating the water and completing the closed system that is sustainable and efficient. The closed, constantly circulating system is what
makes aquaponics especially sustainable for desert gardeners. Because the same water cycles through the fish tank and subsystems, there is no water wasted or lost, except through evaporation.
Once the tanks are filled, the system never needs to be drained. Because the byproducts from the fish create the nutrients for the plants, the longer the water and nutrients remain in the system, the more productive it becomes. “What is really fun about this,” Herbert-Fort says, “is once your system gets cycled, which usually takes two to six weeks to create nitrates from the fish solids, the system becomes more and more productive. I come out here every morning and notice growth.”
Aside from the environmental and sustainable benefits of aquaponics farming, there are tremendous health benefits to growing plants and fish in allnatural, symbiotic aquaponics systems. Because both plants and fish are sensitive to impurities and rely on the natural process of waste production from the fish and filtration from the plants, no fertilizers, pesticides or chemicals can be added to the systems. Any addition of medicines or chemicals for the fish will jeopardize the plants, just as any fertilizers or pesticides for the plants will filter into the water and contaminate the fish. “Because we have this combination of nutrients and fertilizers, chemicals cannot be used,” Herbert-Fort states.
“It’s natural by design,” he says, thus making aquaponics systems sustainable and economical, while efficiently producing healthy, all-natural fish and produce in a Zen-like ambiance.
For more information about aquaponics systems, call Local Roots Aquaponics at 765-276-6427 or visit LocalRootsAquaponics.com. Look for
tour information and produce from Local Roots Aquaponics at the local Farmers Markets.
Tanner Jones is a teacher, environmentalist and freelance writer, located in Tucson.