A few weeks ago, we took a field trip to the Food Systems Lab at Cylburn Arboretum, an urban teaching farm operated by the Johns Hopkins Center for a Livable Future (CLF). On this trip, we visited their greenhouse that holds an aquaponics system, a type of agriculture that combines fish farming with hydroponic plant farming. While their fish tanks are typically home to up to 30 tilapias, the tanks have been emptied for this growing season. Although not true aquaponics, they are able to circumvent the use of fish by adding “fish waste” into the tanks (which you can buy on Amazon!). By doing this, they are still able to produce vegetables in the hydroponics systems. Most plants seem to be able to thrive in the water, with their roots extending down into the water and using the fish waste nutrients. At the Food Systems Lab, they have been testing what plants are successful in this system, with their best success being sorrel. If plants aren’t able to thrive in the hydroponics system, they try growing the plants in different medium, such as rocks placed in a table where water from the aquaponics system can flow. I was most impressed with how they were able to reduce water usage by cycling the water used by plants back into the tanks to reintroduce nutrients. The set-up is surprisingly simple, yet still intricate in their thoughtfulness for sustainability.
The Food Systems Lab is open to the public for tours on Wednesdays 10AM-noon and Sundays 1-3PM. Check out their website (linked here) for more info.