UNIVERSITY PARK, Pa. — After spending five days this spring studying aquaponics at the University of Arizona, College of Agricultural Sciences student Jessica Foster and greenhouse manager Scott DiLoreto are developing the first aquaponic system at Penn State.A junior horticulture major with a minor in wildlife and fisheries science, Foster transferred to Penn State from Salem Community College in New Jersey, hoping to learn more about hydroponic and aquaponic systems. When she arrived on campus last spring, she contacted DiLoreto to discuss the prospect of creating her own aquaponic system. “I gave Jessica and her family a tour of the greenhouses when they initially visited Penn State, and I was able to work with her again while she was taking horticulture classes with a greenhouse component,” DiLoreto said. “She expressed an interest in working with aquaponics from the very beginning.”
Interest didn’t wane
DiLoreto explained that while other students often express interest in starting similar projects, he was particularly impressed by Foster’s drive.“She was pretty serious about it. You could tell she had read a lot and had really thought it out. It’s uncommon to find someone who is that motivated.” Aquaponics is an integrated fish-culture and plant-propagation system that relies on a symbiotic relationship between fish and plants. Fish, such as tilapia — grown for human consumption — are cultured in tanks. Those tanks are connected to a hydroponic plant-growing area. The tank water, which becomes rich in fish wastes as the fish grow, flows to the hydroponics system, where the plants take up and utilize the nutrients in the waste, growing vigorously. The fish wastes, especially the nitrogen component, are toxic to fish, so the plants perform a service to the fish by purifying the water. The clean water is then pumped back to the fish tanks — and the cycle continues. Aquaponics differs from hydroponics in that hydroponics relies on the addition of nutrient salts to the water to grow plants, rather than relying on the nutrients naturally occurring in fish waste. “Aquaponics is the coupling of two biological systems,” DiLoreto explained. “The plants feed off the fish and the fish purify the water for the plants — so at the end you have two products, fish and plants. It’s a much more natural process.” He noted that sustainable methods are used in aquaponic greenhouses. “You can’t use most pesticides because they’re toxic to fish,” he said. “One needs to focus primarily on biological pest management.” DiLoreto added that he believes aquaponic systems go hand-in-hand with increased interest in greener, sustainable agricultural practices and organic and locally grown foods.
The Penn State system
Current plans for the Penn State aquaponics system include using two 300-gallon tanks to grow tilapia, and a large hydroponics area where basil, lettuce, mustard greens and micro-greens will be grown.Foster, who hopes to start her own aquaponics business after she graduates, said there’s definitely a market for aquaponics. “People already have begun growing things this way,” she said. “It’s just exciting to know that I have the opportunity to expand upon it.” Foster and several other students this fall will earn independent study credits for their work on the aquaponics project.