What do ornamental koi fish have in common with a head of lettuce? Just ask three friends who grew up together in Glastonbury and returned after college to establish an innovative farming system. Their answer is aquaponics.

Spencer Curry, Kieran Foran and Matt Braddon are self-appointed "aqua-pioneers" who are beginning their second full growing season as Fresh Farm Aquaponics, a Glastonbury-based benefit corporation (www.freshfarmct.org).

It started when Curry picked up an aquarium, a bag of sand and four little bags of goldfish a few years ago. He brought them home on a Boston city bus to an apartment he shared with Foran. They experimented with a desktop system, amazed to find they could grow tomatoes and lettuce indoors.

Last year, they produced over 1000 heads of lettuce. They sold hundreds of bags of herbs of wheat grass, parsley, basil, chocolate mint, oregano, cilantro and sage. They sell through a community supported agriculture (CSA) and at a winter farmer's market. Their 5,200-gallon deep water culture system consists of six beds located in a greenhouse at Robb's Farm on Foote Road in South Glastonbury.

"The system is capable of holding 2,200 heads of lettuce at any time," said Foran. "It could theoretically produce 16,000 heads of lettuce per year."

But what is an aquaponic growing system? It resembles hydroponics in that the plants grow entirely in solution. Both systems are soil-free. But hydroponic systems rely on chemical additions and the produce is generally not organically grown.

"Aquaponics combines hydroponics with aquaculture to produce organic food," Curry said.

These systems generate their own nutrients from fish that live upstream, at the highest point of this closed-loop system. Fish wastes are converted by beneficial microbes in another part of the loop, rendering a clean high-nutrient solution that circulates into growing flats. The system produces all the micronutrients and macronutrients needed to grow a wide variety of food crops.

Some growers farm tilapia and sell the fish for protein. Others sell mature fish for pond life. Spencer Curry says they have no current plans to sell fish for food, but may sell ornamental fish eventually. This year, however, they will begin packaging fish wastes for sale as fertilizer.

"There are a variety of ways to make money from an aquaponics system," Curry said. "The upfront investment is a bit steep, but aquaponics pays for itself in a year or two. It's a fast payback system."

The Fresh Farm farmers also build and install systems for others or consult with people who have built their own.

Braddon is helping The ARC New London County - a Norwich-based organization that provides services for adults with intellectual and developmental disabilities - to explore ways in which they might incorporate aquaponics into their food production.

"Some of our clients and staff identified aquaponics for a trial," said Kathleen Stauffer, CEO of The ARC. "The more we looked into it, the more reasons we found to go forward."

ARC started their experiment about a year ago in Ledyard.

"Now, we're expecting our first full harvest in April and we think we've learned enough to make the system sustainable," Stauffer said. "It's an emerging agricultural technology," she explains. "Since we provide vocational training for our clients and this requires a unique skill set, we look at it as something that could position a person advantageously for employment. It's also a good way to provide additional food for our homes and to help both clients and staff enjoy the therapeutic aspects of gardening."

Fresh Farm Aquaponics is also working with the Durham school system to establish a system.

"We also hope to revitalize an old factory building in Hartford," said Curry. "We're hoping to get an urban farm going to create job opportunities and provide local food and local education."

Curious?

Curry, Braddon and Foran formed a meet-up called Aquapioneers CT that has recently grown to more than 80 members. (See www.meetup.com/Aquapioneers-CT-Aquaponic-Gardening-Group). Or call them at (860) 531-2782.

KATHY CONNOLLY IS A GARDEN WRITER, LANDSCAPE DESIGNER AND SPEAKER FROM OLD SAYBROOK. SHE WILL OFFER A CLASS IN MEADOW DEVELOPMENT AND NATIVE PLANTS ON MAY 30. VISIT HER WEB SITE FOR MORE DETAILS: WWW.SPEAKINGOFLANDSCAPES.COM. EMAIL: KATHY@SPEAKINGOFLANDSCAPES.COM.