Aquaponics Module

What is it?

Aquaponics is the unlikely marriage of farming fish (aquaculture) and plants (agriculture) in a single system. Fish pond water has fertilized gardens since ancient Egypt and in traditional South Asian rice cultivation. But the process was redeveloped for use in recirculating systems in the 1970s. Since that time, it has become one of a trinity of important, emerging urban agriculture methods. Today it is a boon for backyard enthusiasts and social innovators who continually push the boundaries of the technology.

The Shed’s Aquaponics Module raises tilapia and crops in a closed loop of water and nutrients flowing through a soil-less environment.

The Shed departs from many other operations by: Using biochar – a special charcoal – as a carbon negative growing media for plants; hosting composting worms in grow beds for efficient recycling of waste and powering aquaponic operations with renewable energy and rainwater systems.

How does it work?

Aquaponics works because the environmental needs of fish and plants are complementary: Fish produce nutrient-rich waste products which fuel the growth of hydroponic plants.

Composting worms and naturally-occurring bacteria (e.g., Nitrosomonas and Nitrobacters) do the work of breaking down fish waste and converting ammonia into nitrate – a form or nitrogen less toxic for fish and easy for hydroponic plants to take up.

The resulting aquaponic loop strikes a win-win balance of needs: Plants receive the nutrients they require for growth while fish see the waste removal they need for healthy living.

Why is it important?

Aquaponics points to exciting possibilities for feeding cities sustainably. For example, it uses 85% less water than conventional agriculture because it reuses water in a tightly-cycled loop. This feature is especially important in urban and arid areas where water is obtained and treated at a premium. Aquaponics also does not require synthetic fertilizers for plant nutrition or pesticides to safeguard crops. Moreover, supplemental feeds for fish, like earthworms reared in the Shed, help to further reduce its ecological footprint. Particularly when powered by renewable energy and water supply, aquaponics exemplifies the efficient use of resources for local, community-oriented food production.

As in other parts of the Shed, the Aquaponics Module also brings natural biodiversity to the city’s indoors. Ginger and turmeric grow well in the Module’s substrate and give a nod to culturally important plants for cooking and medicinal use. Both plants, for example, are effective antioxidants and anti-inflammatories in addition to cooking staples. Active compounds like gingerol and curcumin are therefore useful for treating ailments from nausea to osteoarthritis. The Shed reminds us of the irreplaceable but dwindling traditional knowledge that is hidden in plain sight in the crops we grow.

Other crops growable in various parts of the Shed engage the senses. Nasturtium is stunningly bright and edible plant. Its leaves, flower and seedpods are all edible with a peppery, mustard-like taste that goes well in a salad or soup. Mint and lavender stand out for their strong aromatics. Easy to grow, mint varieties can be used in cold beverages or even as aromatherapy. Lavender flowers are both beautiful, have a calming effect and are edible in salads, soups, cookies, and tea. Lastly, tactile crops can include the luffa or loofah which is a vegetable from the cucumber family. Luffas can be eaten as a vegetable when harvested young or they can be used as an exfoliating sponge when fully developed.

What Sustainable Development Goal (SDG) are met?

The Shed’s Engineered Wetland contributes to the UN’s Sustainable Development Goal of Industry, Innovation & Infrastructure (SDG 9) by providing water-efficient growing of a variety of foods.

The Shed’s Engineered Wetland contributes to the UN’s Sustainable Development Goal of Responsible Consumption & Production (SDG 12) by providing water-efficient growing of a variety of foods.

What can you do?

Start a mini-aquaponics system at home with your fish tank.

Explore the science and art behind aquaponics through these unaffiliated links:

Compare aquaponics to other methods used in the Shed through this downloadable lesson plan example.