CHICAGO (AP) -- They call this place the Back of the Yards, a neighborhood in the middle of the city once filled with acres and acres of stockyards.
In their heyday, those stockyards gave Chicago a reputation as the world's meat-packing capital -- but also as an environmental and health horror brought to life in the stark images of Upton Sinclair's novel "The Jungle."
A few remnants of that industry remain here today. But the stockyards are long gone, replaced by an industrial park and a mindset that, from now on, Chicago will try to move past those images.
Now, you will find a jungle of a very different kind here.
It's on the third floor of an old meat-packing plant, a humid hothouse, of sorts, filled with rows of greens and sprouts, even exotic white strawberries. Nearby, in large blue barrels, lurk tilapia, fish native to tropical regions.
It's all part of the fledgling world of urban "aquaponics," vertical farms set up in old warehouses, where plants and fish are raised symbiotically. The idea is that water containing fish excrement is used to feed and fertilize the plants, which then filter that water before it goes, through a series of pipes, back to the fish.
"I never really saw myself going into farming -- but this was an opportunity to try something different," says Mario Spatafora, a 24-year-old, spectacle-wearing accountant by training who is vice president of finances at this new Back of the Yards company, known as 312 Aquaponics. The company hopes it will soon be selling fish and vegetable greens to restaurants and at farmer's markets in the Chicago area.
It started when one of Spatafora's childhood friends, now one of four young partners in the business, set up a successful aquaponics system in his apartment when they were in college -- and a business idea sprouted.
"I knew that even in the worst case scenario, if we couldn't make this work," Spatafora says, "a tax job and being an accountant would always be there."
But this was their chance to be young pioneers.
Those in the field say interest in aquaponics has been growing in the last three years -- though mostly on a smaller scale with people who have backyard greenhouses or who live in warmer climates such as Hawaii.
Sylvia Bernstein, vice chairman of the newly formed Aquaponics Association, has seen the spike in interest. She started an online community forum for aquaponics gardeners two years ago. Last February, the site had 800 members. This year, there are about 4,500.
So far, though, only a few are attempting indoor aquaponics on a commercial scale. Besides the Chicago site, there's one aquaponics business in an old crane factory in Milwaukee, for instance, and another in a warehouse in Racine, Wis.
"These guys are really on the cutting edge," says Bernstein, who is also an author and aquaponics equipment supplier in Boulder, Colo.
Chicago Mayor Rahm Emanuel, a fan of vertical farming, has noticed and taken an interest in aquaponics.
"The mayor correctly believes that it can have a tremendous impact on these neighborhoods, both in terms of jobs and healthy food," says his spokesman Tom Alexander.
Emanuel recently visited 312 Aquaponics, which shares its old meat-packing plant building with such tenants as the Living Well Brewery, where fermented tea called kombucha is made, and the New Chicago Beer Co., a microbrewery that will open later this year.
The sunny space that 312 Aquaponics occupies has high ceilings and brick floors and warm, moist air. In it, visitors find rows of flats under grow lights. Many of those flats are filled with lettuce and "microgreens," tiny plants, such as basil or beets, that are grown closely together in hydroponic containers and used much like sprouts in salads and sandwiches.
Once the plants are ready for market, the flats will be covered and distributed to restaurants live so they stay as fresh as possible, says 23-year-old Andrew Fernitz, a biology major in college who is another of the 312 partners.
Fernitz dunks a net into one of the barrels, pulling out two skittish tilapia. "They are a hearty fish," he says, chosen, in part, because they can better withstand fluctuations in water temperature.
There are, of course, challenges to getting an old building like this up to code. There are cracks in the floor or ceiling that are being repaired and occasional drips in the pipes that supply water to the system. The entire process has to be licensed by the city health inspectors and other departments.
"Technically, we're a farm," Spatafora says. "But nothing in the Chicago business code regulates farming. The closest thing they've got is a restaurant, and clearly, we're not a restaurant."
Retooling an industry -- and creating business for a new era -- isn't easy, everyone acknowledges. But the mayor is committed to helping entrepreneurs sort out licensing issues, his spokesman says.
Still, some still question if it's worth all the trouble.
"I don't want to be overly negative. It's very interesting technology. It's all the rage and all the buzz," says Dan Vogler, a trout farmer in northern Michigan, who is also president of the Michigan Aquaculture Association.
"But whether or not it can be done economically, I don't know."
One urban aquaponics business called Natural Green Farms, in a former plow factory in Racine, Wis., did temporarily close this year after a failed expansion -- though its owners are vowing to grow the business back up.
With the potential for a seafood shortage in the next five to 10 years -- and most of the supply coming from overseas -- Vogler says government officials should be focusing more on farms dedicated to raising fish only, often in bigger quantities.
"Take a look at species that we are already good at growing, using technologies we already know how to do," Vogler suggests. He says those species include trout and salmon, shrimp, catfish and crayfish.
But those types of fish farms also can have a different set of challenging issues, including the fact that the water used in them, once dirty, is often flushed away, says Todd Leech, vice president at Sweet Water Organics, the urban aquaponics business in Milwaukee.
In 2010, the company, housed in the old crane factory, began selling perch and other fish, as well as greens, such as lettuce, spinach and chard, to restaurants and grocery stores, and at farmers' markets.
Leech says they've found an economically viable model and now reached "break even" status.
In fact, Milwaukee is developing a reputation as an urban aquaponics leader, helped along by a nonprofit called Growing Power that received a MacArthur Foundation grant and developed the aquaponics model that Sweet Water has used.
One of the biggest expenses to overcome, Leech says, is electricity to run the grow lights for the plants. Increasingly, he says indoor aquaponics businesses will have to look for solar and other options if they want to maintain their indoor businesses.
To help offset electricity costs, Sweet Water also is setting up greenhouses on land outside their warehouse -- and as a result, expects to turn a profit this year, Leech says.
That sort of success is a little ways off for 312 Aquaponics, whose young owners have had to find part-time jobs, while they wait to complete the licensing process.
Even young pioneers have to pay the rent.
So one of the partners is doing website development. Spatafora is doing taxes of friends and family members. And Fernitz is doing some bartending.
"Yeah, I gotta go serve and dole out some drinks for a while," Fernitz says, smiling, "which is just fine."
Regardless, they are sticking by their goal to be selling at markets by summer.
"We don't want to be on the sidelines while everyone else is out there at the market, in the grocery stores, putting their food out there...," Spatafora says. "We're ready to get going."
312 Aquaponics site: http://www.312ap.com/home/
Growing Power: http://www.growingpower.org/
Sweet Water Organics: http://sweetwater-organic.com/
Aquaponics community forum: http://www.aquaponicscommunity.com