Camden High School (CHS) earth science students are learning how to build and sustain an aquaponics greenhouse as a part of their class curriculum.
Earth Science teacher Joey Hendrix said he started an aquaponics system at his house, then brought it to school for the students to run. When the system got too big for the classroom, they decided to build a greenhouse.
Students began working on the frame of the greenhouse in October and finished in December. Construction on the inside began in January and was completed in April. The greenhouse has removable plastic siding that will help keep heat in during the winter. All of the wood in the greenhouse was donated. Hendrix’s earth science class spends about two hours a day in the greenhouse currently. Over the summer, he and his aquaponics partner Scott Lemons will maintain the system. Lemons has instructional knowledge on putting aquaponics centers together, Hendrix said. Lemons helped Hendrix build the original aquaponic system in Hendrix’s backyard.
“Aquaponics is a very small world right now,” Lemons said.
With aquaponics, people are able to grow plants and fish together in one soilless and integrated system. Fish and water are the main components of an aquaponics system. CHS has Koi and Tilapia, as well as crawfish. The fish put nutrients into the water, which is then pumped throughout the green house and supplies nutrients to various grow beds in the green house. The plants filter the water so clean water goes back to the fish. Nutrients are produced by way of waste and molting which fertilizes the water. All of the water used in the greenhouse is rain water collected from the roof of CHS. The greenhouse has three water tanks: two are covered underground, which people can walk over, and one that is referred to as the lily pad pond. Each time it rains, students drain the water from the tanks and add new water to the system.
There is a big difference in the nutrients of plants that are grown through aquaponics than plants grown hydroponically. Hydroponics uses water and chemicals, so you have a large plant, but little nutrients.
Lemons said they are just trying to produce a product right now, but with negotiations with the school district, they may try sell their product in the future.
“Consumers are conscious of where they get their food from,” Lemons said. “With the ease of growing and harvesting, we will be able to produce healthier food at lower cost and sustain a local food supply.”
Hendrix said there isn’t much evaporation and there aren’t many pests because there is no soil. The maintenance is easier, Hendrix said, so the goal is to produce 1,000 to 2,000 heads of lettuce a month. The greenhouse houses 500 grow beds. The greenhouse is also home to 200 pounds of Tilapia. Hendrix and his students will breed the fish to bring that number to 400. They created a hatchery, where adult fish will breed and eventually be removed to allow the smaller fish to grow. Right now the fish are eating fish food and some water plants, so the fish produce more waste. Hendrix hopes to get to the point where they can feed the fish water plants only to cut down on costs.
There are several stations in the greenhouse. There is a seed station, where the growing process begins; an aeroponics table -- a way of growing plants without soil using air or a mist; and the grow bed. The process takes about six weeks from start to finish, Hendrix said.
“We shouldn’t ever be without plants in the system,” Hendrix said. Getting used to the system requires a daily measure of water dynamics and temperature, tasks Hendrix assigns to students.
“There are several things they are learning that will help them even if they don’t go into farming,” Hendrix said. “There are small systems they could create in their backyard, large systems they could turn into a business, or it can just set the foundation for further science studies.”