Out back, Meir Lazar is putting the finishing touches on a bigger new home for the fish inside a plastic-covered greenhouse. There, he hopes, the waste from the fish he's tending will help him raise enough lettuce, tomatoes and other produce to feed his family of five year-round.
Sustainability is more than a buzzword for Meir Lazar, 32, a computer systems administrator and teacher who's pursuing aquaponics in his small suburban backyard off Greenspring Avenue. He said he's inspired at least in part by news reports about food tainted by pesticides, bacteria and even radiation from the Japanese nuclear reactor meltdown earlier this year.
"I think it's incumbent on every person to start growing their own food so they can take back some of the control over their health, over what's in their food," he said. "There, at least, you know it's pesticide-free. … Plus, you have a deeper appreciation of what you've grown and what you're about to eat."
Aquaponics has been around at least since the early 1970s, when the New Alchemy Institute in Massachusetts started promoting backyard fish farming and organic gardening inside greenhouses it dubbed "bioshelters."
It's gained new attention in recent years, not just from advocates of sustainable agriculture but from those who believe aquaponics can help fill needs in poor urban communities for healthier food and jobs. The model for that is Growing Power, an urban farm and educational foundation in Milwaukee started by Will Allen, who grew up on a farm in Maryland.
In the Baltimore area, though there may be others raising fish and vegetables together in their basements or garages, few are doing it on a larger scale.
That may be about to change. Karl Roscher, aquaculture coordinator for the Maryland Department of Natural Resources, said he's reviewing applications now for two new commercial aquaponics operations locally. One is to raise giant freshwater prawns at the Baltimore Free Farm in Hampden, he said, while the other aims to produce thousands of tilapia a week and scads of fish-fertilized produce on Farmer Tom's turkey farm in Reisterstown.
"I've always wanted a farm that is self-sustainable," said Tom Reynolds, who with partner John Chapman has adapted part of the hay barn on his 172-acre farm to raise tilapia and feed the nutrient-rich wastewater to vegetables being cultivated hydroponically under grow lights in water-filled beds.
Reynolds said he's always been interested in fish farming. But with deer devouring his corn and soybeans and suburbia slowly replacing farms all around, he said he figured he needed to try something new to stay on the land his family has farmed since 1952.
Tilapia are a popular choice for fish farmers, partly because of their commercial appeal, but also because they're relatively fast-growing and hardy.
There's also a third aquaponics venture taking shape at Cylburn Arboretum in northern Baltimore, which has yet to apply for an aquaculture permit from the state. Sponsored by the Johns Hopkins Center for a Livable Future, it would raise tilapia and produce for sale in the city's "food deserts," where fresh locally grown produce isn't readily available at corner markets and convenience stores.
With a budget of about $10,000 and the help of interns, friends and volunteers, microbiologist Dave Love has assembled his fish and produce farm. Four blue 250-gallon plastic tanks will be used to raise tilapia, he explained. The fish excrement and nutrient-fouled water are to be piped from the bottom of the tanks into a couple other tanks where the ammonia in the wastewater is converted by bacterial action into a form of nitrogen that can feed plants. The enriched water is then to be piped through two large shallow troughs in which Love plans to raise leafy greens and other vegetables. Thus cleaned up, the water is then pumped back to the fish tanks.
"It's sort of like the next step into urban agriculture," Love said.
It's also a new direction for the center, which has done studies and published reports highlighting environmental and health risks associated with "industrial" agriculture and even large-scale fish farming. Now, according to Love, the center wants to show how food can be produced sustainably, though to keep costs down he hopes to rely on volunteer help in tending the fish and produce.
"Some might say this is not sustainable," Love said, as he worked with volunteers Gary Jenkins and Curt Millington to line the wooden tank that's to be used to dechlorinate fresh water for the fish tanks. "But we need to try."
Love said he hopes to put fish in the tanks by spring, and to open the operation to researchers, visiting school groups and others. Before the year is out, if all goes well, the center's aquaponics operation will be producing 120 pounds of tilapia for consumption every six weeks.
Lazar said if he can feed his family this way, anyone can.
"I've always had a love of gardening," he said, "but didn't have a green thumb."
He started out with a hydroponics garden a few years back, he recalled, then tried his hand a couple of years ago with an indoor aquaponics operation — in their basement bedroom — after a friend turned him onto it.
Leah Lazar, 28, said she enjoyed the soothing sounds of the fish tank in their bedroom, decorated with two-foot tomato plants and other greens.
"It was also nice when I'm cooking to go and get some chives from in there," she said.
Lazar decided this year to scale up and moved his aquaponics operation to the backyard in the spring, raising his fish at first in an in-ground pond. He said his neighbors weren't wild at first about how he was transforming his backyard, so he's worked to win them over with some homemade jam. And he said he's entertained Baltimore County code inspectors twice, so far with no repercussions.
Once cold weather hit, though, Lazar said he realized he needed to enclose his entire operation. Tilapia are tropical fish and will start dying if water temperatures dip to 50 degrees Fahrenheit. His turned belly up one frigid day recently, though many revived once rescued and moved indoors.
He figured he's spent perhaps $3,000 on a 20-by-20-foot hoop greenhouse, six 55-gallon plastic drums for raising his fish, and a dump-truck load of pea gravel for his six garden beds made from used, cut-up plastic bulk containers. A few kale plants, shallots, spices and Bibb lettuce remain, but a new crop of radishes is starting to peek up through the gravel.
Before he can finally reinstall the tilapia, though, Lazar has to complete construction of a "rocket mass heater," a special type of wood-burning brick fireplace, to keep the water warm enough. Once everything's finished and fine-tuned, Lazar said, he hopes to be able to harvest 100 full-sized tilapia a year from his operation, and plenty of greens.
"It doesn't look like much, but it works," he said, as water trickled from hoses into each of the big garden beds. "I want to show that anybody can do it."