Rainbow Trout Performance in an Intelligent Aquaponic System
- Abstract
Chris Vasdravanidis 1, Dimitris Papadopoulos 2,3, Ioanna Chatzigeorgiou 3,4, Athanasios
Lattos 2,3, Ioannis A. Giantsis 1 and Georgios K. Ntinas 3,4
1
  Dept. of Agriculture, Faculty of Agricultural Sciences, University of W. Macedonia, Florina, 53100, Greece
2
  Dept. of Biology, Faculty of Science, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece
3
  Oecon Group, Business & Development Consultants, Frixou 9, Thessaloniki, 54627, Greece
4
  ELGO-Dimitra, Institute of Plant Breeding and Genetic Resources, Thessaloniki, Greece


                Summary 1
                Growing population, climate change, overexploitation of environmental resources and food
                security issues, drive the need for innovating food production within a sustainability corridor.
                Aquaponics, combining the technology of recirculation aquaculture systems (RAS) and
                hydroponics in a closed-loop network, could contribute to addressing these problems.
                Aquaponic systems have lower freshwater demands than agriculture, greater land use
                efficiency and less harmful environmental impact combined with higher productivity. As a
                result of the great need for sustainable food production aquaponics is rapidly developing.
                However, there is limited research in economical feasibility of these systems and lack of focus
                on commercial implementation. Integrating new technologies may result in intelligent
                monitoring and control of the production, making these systems more intensive, accurate,
                efficient and finally profitable, attracting more investments.
                The present paper focuses on the potential of hydroponic cultivation of vegetables along with
                rainbow trout (O. mykiss) utilizing intelligent monitoring of the system. Oncorhynchus mykiss
                is a psychrophilic species that requires temperatures between 14-20 °C, high clarity water and
                also high oxygen levels. Rainbow trout has significant commercial value, high growth rates
                and great feed conversation ratio. The aquaponic system used in this study is vertically
                operating. Two rearing tanks (1500 l) are located in the basement of the greenhouse along with
                mechanical and biological filter. Water supply comes from a rainwater tank, passes through
                the fish tanks and the filters and communicates through pipes with the upper greenhouse, where
                the water from fish tanks is used to fertilize the plants. In 10 th of May 2022, 1080 juvenile
                rainbow trout were introduced from a breeding station.
                Initial body weight and total length were 5.1±0.33 cm and 1.19±0.18 gr respectively. Fishes
                were stocked in biomass 0.45 kg/m3 and a stocking density of 360 fishes/m3. Daily feed
                amount was 3% (grams of food per gram of total fish biomass) and was provided in 5 equal
                food rations by automatic feeders. Every week, the fishes were weighted, and the daily amount
                of food was adjusted accordingly. At the end of the 28 days, body weight and total length of
                the fishes were measured. Survival rate of the fishes was calculated at 97.2 %. Specific growth
                rate of body weight was 3.1% per day and specific growth rate of total length was 0.81 % per
                day. Over the 28 days of the ongoing research, the mean room temperature was 17.65±1.22
                °C, carbon dioxide at 374-811 ppm and the humidity 53-56 %. The water temperature was
                around 18.72±0.84 °C, the conductivity of the water was 323 𝜇𝑠/cm, pH was 7.5 and the
                dissolved oxygen was between 6.2 and 7.0 mg/l. The concentration range of total ammonia
                nitrogen, nitrite and nitrate were 0.06-0.25 mg/l, 0.059-0.25 mg/l and 5.0-37 mg/l respectively.
                To sum up, this research presents the application of an intelligent aquaponic system.
                Automizing feeding and digital monitoring of water flow, fish behavior, environmental

Proceedings of HAICTA 2022, September 22–25, 2022, Athens, Greece
EMAIL: chrisvasdra@outlook.com.gr (A. 1); dimipap93@hotmail.com (A. 2); ichatzigeorgiou12@gmail.com (A. 3); aqualattos@gmail.com
(A. 4); igiantsis@uowm.gr (A. 5); gntinas@ipgrb.gr (A. 6)
ORCID: 0000-0002-1257-7654 (A. 1); 0000-0002-8822-2665 (A. 3); 0000-0002-0773-9604 (A. 4); 0000-0002-6323-2955 (A. 5); 0000-0001-
5205-9387 (A. 6)
             ©️ 2022 Copyright for this paper by its authors.
             Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).
             CEUR Workshop Proceedings (CEUR-WS.org)




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conditions, and water parameters by using automatic feeders, surveillance cameras and
recording sensors offered integrated management of the system. The high survival rate along
with the adequate growth of the fishes are great signs of a well operating system.

Keywords
Aquaculture, hydroponics, rainbow trout, internet of things




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