Food out of water

Mainstream aquaponics faces economic and environmental challenges

Aquaponics systems depend on fish and plants co-existing.
Photo courtesy Sylvia Bernstein

Mickey Mouse has never been known for his green thumb, but a ride dedicated to aquaponics at Disney’s Epcot Center (surely a death-defying thrill) highlights the public curiosity for this growing trend. While an increasing number of people take an interest in aquaponics as a way to grow crops and fish — and Longmont is seeing the opening of a 7,400-square-foot aquaponics store — industry professionals continue to wrestle with some of the lingering issues with the sustainability of this practice. From Disney World to local businesses like Longmont’s Aquaponic Source Group and 63rd Street Farms, these groups must hash out concerns regarding the economic feasibility of aquaponics, consumer safety standards and sustainability issues regarding ocean-harvested fish meal.

At the aquaponics exhibit at Disney World, passengers float on a stream through a jungle of plants and vegetables, with fish beneath the ride whose waste provides nutrients for the plants suspended above the water — no soil or external fertiliz-er necessary. But Disney World, which has pockets much deeper than most commercial farmers, runs its facility purely for the entertainment of its guests and not to sell food. The volume and substance of their yield isn’t important. For farmers, on the other hand, it’s their livelihood.

Avery Ellis, an aquaponics specialist who lectures in permaculture design courses throughout Colorado, and who received a master’s degree in ecological design from the San Francisco Institute of Architecture, is working through the economics of an aquaponics facility with 63rd Street Farm in Boulder, which plans to open a 1,000-square-foot aquaponics greenhouse next year.

Ellis must figure out how to turn a profit on a yield he expects to cap out at 100 heads of greens a week and 1,000 fish a year.

“Who’s making a living off of a 1,000-square-foot greenhouse? Sure, it might produce $20,000 a year worth of produce, but it might cost $5,000 to maintain, and there has to be somebody to operate the system. It’s not necessarily paying the bills,” says Ellis. “That’s not even a livable salary for one person.”

The primary reason Ellis and 63rd Street Farm think they’ll find success through aquaponics is that their permaculture farm already has multiple sources of revenue. Permaculture is characterized by stacking functions — or using the functions of one aspect of the farm to service another. So a farmer might use goats or cattle to fertilize and enrich the soil before rotating in a nitrogen-rich legume crop, which further enriches the soil for next year’s planting season. The waste from that year’s harvest might be used for chicken feed. Ultimately, the risk associated with their aquaponics system is covered by revenue from other parts of the farm.

“[Aquaponics] need to be in a setting with multiple revenue streams because when you’re talking about a single revenue stream, one effluent could bring the whole thing crashing down,” says Ellis. “That often happens to farmers in general, when they put all their eggs in one basket — in fact, that saying is appropriate.”

One issue Ellis won’t have to worry about is what to do with his yield. At just 100 heads of greens a week, there’s enough demand through 63rd Street Farm’s community support agriculture (CSA) program, farm stand and the Boulder farmers’ market to sell the entire harvest. But larger aquaponic facilities, which might produce up to 5,000 heads a week, need to sell to larger commercial vendors. In order to do that, aquaponic farms must pass the same safety standards as conventional outdoor farms. Because the plants come into direct contact with fish manure, that challenge is yet to be met.

“In traditional ag, you couldn’t take cow poop and stick it next to your crops without it having to go through the proper composting process,” says Gina Cavaliero, managing director for Green Acre Aquaponics and former chair of the Aquaponics Association. “It makes sense there, but doesn’t make sense for aquaponics. We’re working on getting science and the data we need as an industry to present to the food safety industry, to say this is food, and it’s absolutely food safe. Here’s what we propose and here’s an audit we’d like you to use for our farms.”

Aquaponics requires less energy and external inputs than soil farming, especially if systems take advantage of natural light. Because water is pumped throughout the system, and doesn’t need to be replaced, aquaponic systems use less water than soil agriculture. Yields can be harvested much quicker, too. Lettuce might take 15 weeks in soil, but nine to 10 weeks in an aquaponic setting. But a growing sustainability concern comes from the primary external input into an aquaponic system, fish feed, which often comes from ocean-harvested fish.

“Part of the reason why people are turning to land-based recirculating aquaculture is to relieve some of the tension off the ocean, which is being overfished,” says Sylvia Bernstein, president and founder of the soon-to-open aquaponics center The Aquaponic Source, and author of Aquaponic Gardening: A Step by Step Guide to Growing Fish and Vegetables Together. “But then we turn around and pull fish out of the ocean to feed fish on the land. That’s probably not the way we want to go long term.”

Bernstein says that some aquaponics facilities are experimenting with spent grains and yeast from beer breweries as a fish meal alternative, with signs of success. In 2010, Colorado-based Oberon FMR, Inc., a fish meal replacement manufacturer, signed a deal with Miller-Coors to turn 5,000 tons of beer sludge into 6,000 tons of fish food flakes, although it was only a one-time contract for a pilot project.

Another alternative protein source for fish feed is soy, but the process is still gaining traction.

Bernstein says she hopes to serve the growing individual interest in aquaponics, as her company hosts its grand opening from 2 to 5 p.m. on Oct. 5 at 1860 Lefthand Circle, Suite E, in Longmont.

The new center will feature an education and research center, retail equipment for at-home aquaponics and aquaponic system demonstrations.

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