Exploring the Potential for Northern Aquaponics at Victus Farm
What do you get when you combine aquaculture (raising fish in tanks) with hydroponics (cultivating plants in water)? Aquaponics! While ancient societies such as the Aztecs and groups in Southeast Asia have long used this variety of farming, the U.S. has witnessed a revived interest in growing fish and plants together, concurrent with a push for sustainable, organic and local food production.
Curious about the potential for creating financially stable aquaponics facilities in northern climates, Minnesota Sea Grant staff visited with Mike Mageau, Assistant Professor of Environmental Studies at the University of Minnesota Duluth, at Victus Farms. Mageau developed Victus Farms, a 9,000 square-foot complex dominated by a large greenhouse, as a "proof-of-concept" venture involving the University and the City of Silver Bay. It was designed in 2012 and, in it's short life, Mageau reports that he has learned something new almost every day.
Mike Mageau tends to lettuce in the aquaponic tank.
Some lessons were tough: growing organic lettuce, basil and tomatoes has a better return on investment than rearing tilapia, which is more work and more prone to failure. About 80-90 percent of the farm's sales are lettuce, basil and tomatoes.
Some lessons were exciting: people really want locally grown organic food options. Mageau says there is much more demand than product.
Tilapia and lettuce share the same water in Silver Bay, Minn.
Victus helped contribute to cutting-edge research on aquaponics in its original model of cultivating tilapia, lettuce, and algae for biofuel in a symbiotic environment. However, over the years Victus researchers tweaked this and adjusted that in an effort to balance scientific inquiries with economic reality. The extensive processing and energy required to convert the algae into burnable oil quickly trumped any economic benefit from cultivating algae. Victus removed biomass boilers in favor of cheaper and more effective traditional heaters.
Chief benefits of Victus's design are its sustainable practices and systems that fit easily into the aquaponics model. Plants begin their life at Victus in traditional soil based seedling plots in a controlled environment. Once developed, seedlings grow next to fish in the same giant tubs, allowing nutrients and water to be conserved with minimal loss. All of the water used to raise the fish and plants is supplied from rainwater collected on the greenhouse roof and the farm uses less than 10 percent of water needed by conventional fish farms. Victus reduces its environmental impact by only supplying fish and produce to businesses within 60 miles of the food's origin. Though the farm is a model for what might contribute to a sustainable society, Mageau believes Victus's local, fresh food is ultimately what attracts shoppers.
Now three years into the experiment, how successful has Victus truly been? One could argue success is reflected in the current high demand for products and the valuable lessons learned for future aquaponics development. Others might argue that Victus lost its original aquaponics vision in favor of a less exciting hydroponic operation. Maybe success is measured by the interest of others. Not only is Victus serving as a platform for improving society's ability to grow food in cold climates, but it has provided training opportunities for students, research opportunities for faculty, and it serves as a model for businesses looking to start their own aquaponic systems. While aquaponics systems will improve as best practices are established, Mageau encourages individuals to try constructing their own private aquaponics systems. With a bit of engineering and ingenuity he thinks there is great potential for a future that involves innovative ways of producing fish and produce together.
By Nick Wahl