If your children find it hard to like and eat nutritious leafy greens, just tell them to act like a fish! The Zoo’s aquarium fish actually love leafy greens. In fact, romaine lettuce is their food of choice. They also enjoy bok choy, collards and kale. Most of the leafy greens are delivered to the Aquarium by the Zoo’s commissary team. But to encourage this passion for plants, the aquarium team custom built a small aquaponics system so the Zoo could grow some of its own leafy greens.
Aquaponics is a simple and efficient way of farming plants and fish together. The fish provide nutrients for the plants with their waste. In turn, the plants keep the fish’s water clean by removing the fish’s waste. An aquaponics system is made up of two parts: the water where the fish live and a separate area where the plants grow. A pump moves water back and forth between the two areas. At the Zoo, our aquaponics plant tray is full of special clay pellets and helpful composting worms which encourage the plants to grow. We grow a mixture of spinach, sweet potatoes, basil, parsley and lettuce.
The real stars of the aquaponics system are the tilapia fish. Although tilapia are a common food found in grocery stores, we chose to display them because they are a hardy fish and commonly found in aquaponics systems. We also thought people might be curious what they looked like outside of the grocery store and in a natural habitat. Our tilapia are energetic and always searching for a snack. If a zoo keeper’s fingers get to close to the water, the tilapia have been known to swim right up and try to nibble on them.
Zoo guests can enjoy the aquaponics system in the lower gallery of the Aquatics building. The system is easy to spot because the top half is packed with bright green plants and the bottom half is filled with fish. So come and see how our fish are staying healthy and fit--by eating their leafy greens!
Outside of the zoo environment, aquaponics has become a popular way to farm human food as well because it is sustainable and environmentally friendly. Several farms in Oklahoma City use aquaponics to grow plants or fish for human consumption. If you want to learn more about sustainable seafood or aquaculture, check out www.seafoodwatch.org.
--Danielle Woolen, animal caretaker