Urban farming meets fresh fish

More urban gardeners are incorporating aquaponics for more sustainability

From small backyard gardens to larger community spaces and rooftop ventures, urbanites are rediscovering the value and freshness of home-grown food.

Aquaponics is a new trend that’s making headway that promises to enhance the quality of urban gardening while adding an unusual supply of sustainable protein.

Aquaponics is the cultivation of fish and plants together in a constructed, re-circulating ecosystem that uses natural bacterial cycles to help convert fish wastes into plant nutrients. With pesticides, bacteria and even radiation from the Japanese nuclear reactor meltdown last year all having an effect on our food, growing your own food has become more important to an increasing segment of our population.

Fish suited to aquaponics include tilapia and catfish photo by Ryan Somma, Flickr

Back in the ’70’s, Massachusetts’ New Alchemy Institute began promoting backyard fish farming and organic gardening inside greenhouses that it dubbed “bioshelters. A quick search on the internet of aquaponics shows that it’s once again gaining a foothold both in the availability of ready-to-use kits, courses and various commercial and residential systems.

The past few years it’s been embraced by those who feel it can fill a need in poor urban communities to have healthier food and more jobs. The model for this has been Growing Power, Milwaukee’s last fully functional farm within its city limits. This combination farm and educational foundation was started by former Maryland native Will Allen.

The Baltimore area already has a number of commercial and residential-based aquaponics farms  Karl Roscher, aquaculture coordinator for the Maryland Department of Natural Resources, says he’s reviewing applications for two new commercial aquaponics operations locally.

Even Johns Hopkins is jumping on the bandwagon.

Aquaponics irrigation at Growing Power photo by OrganicNation, flickr

The Johns Hopkins Center for a Livable Future is sponsoring an aquaponics venture taking shape at Cylburn Arboretum in northern Baltimore which will raise tilapia and produce for sale in the city’s “food deserts,” where fresh locally grown produce isn’t readily available at either corner markets or local convenience stores.

Fish farming with aquaponics is a closed-loop system. Fish grown inside large tanks excrete waste, which is pumped from the tanks bottom into other tanks. The ammonia in the wastewater is converted via bacteria into a form of nitrogen that can feed plants. This enriched water can then piped into various planters containing live plants such as leafy greens or other vegetables. Cleaned and filtered, the water is then pumped back to the fish tanks.

Urban gardeners who loves fish may want to consider expanding into aquaponics. It may mean substituting a garage for a greenhouse, but it could be a healthy and educational addition to your lifestyle.