Imagine growing vegetables and fish in the same space. That's the idea behind aquaponics, a marriage of fish farming and soil-less plant cultivation in a single, sustainable closed system.
Supporters believe aquaponics can play a key role in alleviating food insecurity, addressing the problems of climate change, ground water pollution and overfishing.
Recirculating wetlands system
Aquaponics is really as old as nature itself.
"Aquaponics is really a recirculating wetlands system, so it's happening right on the banks of our lakes," says Sylvia Bernstein.
Bernstein was a hydroponic gardener for years - growing plants without soil using a water-soluble chemical fertilizer - before discovering she could use the waste water from fish to grow organic vegetables and fruits.
"Honestly, I was very skeptical and just couldn't believe that something as simple as fish waste could become a complete fertilizer," she recalls. "So I had to actually see a system that was in a friend's basement. But when I did, it changed my life."
That was three years ago. Bernstein built her first aquaponics system with her 15-year-old son on a concrete pad outside her home in Boulder, Colorado. In her greenhouse today, she mainly raises tilapia and trout - feeding them once a day.
There are no weeds in her aquaponics garden, and she doesn't have to worry about watering. The plants are growing in containers at a table height for easy access.
"I, just this morning, pulled four radishes and some lettuce for lunch," Bernstein says. "In my greenhouse right now, I grow all sorts of herbs, tomatoes, peppers."
Bernstein started her own business, The Aquaponics Source, with an online store, her own YouTube channel and a blog. She teaches aquaponics at the Denver Botanic Gardens and recently published a book about how to set up an aquaponic garden at home.
According to Berstein, a growing number of people in the U.S. and around the world are doing it, and enjoying the results: a year-round supply of healthful, safe and delicious food.
Earth-friendly food production
The Internet is helping many aquaponic gardeners get connected and learn from one another.
"Aquaponics is a perfect thing to invest one's mind and heart and elbow grease into," says James Godsil, co-founder of Sweet Water Organics, a commercial aquaponics farm in Milwaukee, Wisconsin.
In 2010, Godsil helped set up a foundation to promote the approach.
"The Sweet Water Foundation was dedicated to democratizing and globalizing the information and the methodologies required to advance this very Earth-friendly food production system, which, by the way, only uses about 10 percent of the water normal farming does, and uses no pesticides. It's all natural."
According to Godsil, those advantages have been a powerful incentive for people from all walks of life who are considering a career in aquaponics.
"The Sweet Water Foundation probably has had 500 supporters, including school students, and a community of retired engineers, professionals, social enterprisers, teachers and artists," Godsil says. "There are so many young elders who are retiring and looking for another career for the next 20 years."
Beyond borders
Through collaboration and joint projects, Godsil is carrying the inspiration beyond U.S. borders.
"I was asked to go to Venezuela this March," he says. "And I'm working with people who have a project in Ecuador, I'm working with people in the Congo, in Uganda and Tanzania."
A private group called the Society for Appropriate Rural Technology for Sustainability, is partnering with Sweet Water Foundation on an initiative in India.
"We've formed this Indo-American Aquaponics Initiative, and we aim to make aquaponics one of the fastest growing economic activities in India within a decade," says Subra Mukherjee, secretary of the group, based in Kolkata, India.
Advocates say, with fuel and fertilizer prices climbing and irrigation water supplies dwindling, aquaponics offers a sustainable alternative that can help feed the world's growing population.