An Aquaponic System with Hydroponic Culture of Sweet Potato and Tilapia Culture

Abstract

An integrated system with a hydroponic culture of sweet potato and tilapia culture was assessed as a new combination in aquaponics to investigate its potential and productivity. The first experiment was conducted inside a glasshouse using plastic tanks as water reservoirs to compare the growth and development of two sweet potato (Ipomoea batatas (L.) Lam.) varieties Beniazuma and purple sweet lord using hydroballs, granular plastics, cut rockwool, and rockwool blocks as supporting materials in hydroponic culture. The supporting material was placed inside plastic pots. Greater growth and development of the storage roots of sweet potatoes in both varieties were obtained in hydroballs. In the second experiment, four sweet potato varieties, Kokei 14, Suioh, Beniazuma, and Elegant summer, with hydroballs as the supporting material, were examined hydroponically with an integrated culture of tilapia fish in the pond. Two ponds were 7.7 m and 5.3 m, in length and width, respectively, and water depth was maintained at 0.38 cm. Styrofoam boxes with holes on the bottom side were used to culture sweet potato on the water surface. Nylon net containers filled with hydroballs were placed in the Styrofoam boxes. The variety Kokei 14 produced the greatest fresh and dry weights of storage roots and percent harvest index in both ponds, with and without fish. The number and diameter of the storage roots of Kokei 14 were higher. Tilapia fish were cultured in one of the two ponds and fed artificial feed. The average length and weight of tilapia fishes increased to 10 cm and 188 g, respectively, 143 days after culturing, and those were 1.8 and 6.9 times, respectively, greater than at the start. The integrated culture of sweet potato hydroponically on the water surface and tilapia in pond water increases the food production in a limited space and profitable.