Here's the setup of the Johns Hopkins University aquaponic system at the Cylburn Arboretum in Baltimore, MD. You'll notice that the fish tanks and the plants are across the room from each other. The filtration system, however, is still there, as water gets filtered through tubes from the fish tanks to the plants and back, sustaining symbiosis. It also quells any chance of fish nibbling on the plants' roots.

Here, you can see the water, cleansed of impurities by the plants, is filtered back into the vats where the fish live. These vats house tilapia, who like dark environments that mimic their natural habitats. The netting on top keeps them safe from harm (and from jumping out). They must be fed daily, and can eventually be eaten when fully grown.

A close up of the aquaponic lettuce. As the aquaponic system is technically housed outdoors (in a greenhouse), green leafy plants grow best in the colder months.

Here, you can see the plants are happily growing through recycled styrofoam cooler-tops, which the project saved from the dump. Although styrofoam is not biodegradable, this rescued material works well because 1) it floats and 2) it will not break down, so it can be used indefinitely.

A close-up of the aquaponic Swiss chard. As the aquaponic system is technically housed outdoors (in a greenhouse), green leafy plants grow best in the colder months.

A close-up of the aquaponic bok choy. As the aquaponic system is technically housed outdoors (in a greenhouse), green leafy plants grow best in the colder months.