Implementation of an experimental nutrient film technique-type aquaponic system

Aquaponics has been considered as having great potential as an organic production method of aquatic organisms and vegetables, because the nutrient-rich water from aquatic organisms is utilized for plant growth. The essential elements of an aquaponic system consist of the following five: a tank to maintain aquatic organisms; a clarifier or sedimentation; a biofilter; a hydroponic component; and a sump pump. In this paper, we propose the design and implementation of a nutrient film technique-type aquaponic system, which does not include the sump pump. Aquaponic systems were tested during one production cycle of the Carolina cucumber ( Cucumis sativus ) and Parris Island lettuce ( Lactuca sativa ). The aquatic organism employed was tilapia ( Oreochromis niloticus ). Nine systems were utilized with the aquaponic technique, and the remaining three were utilized with only the hydroponic technique as controls in plant production. The proposed aquaponic system worked efficiently during the entire crop cycle without any problems or deficiencies from lack sump. No changes were made in the flow of water in the aquaponic system during the growing season. Tilapia survival was 97.2 ± 2.4 %. Specific growth and food conversion ratios were 4.95 and 0.99, respectively. In plant survival, there were no significant differences ( p > 0.05) between both production techniques. In lettuce, foliar wet weight, foliar dry weight, and yield were higher ( p < 0.05) in hydroponics. In cucumber, fruit number and yield were higher ( p < 0.05) in the hydroponic system. Fruit length, width, and weight exhibited no differences ( p > 0.05).