Aquaculture Europe 2023

September 18 - 21, 2023


Add To Calendar 21/09/2023 16:00:0021/09/2023 16:15:00Europe/ViennaAquaculture Europe 2023MINT Mentha spicata AFFECTED THE WATER QUALITY, GROWTH, AND MICROBIAL COMMUNITIES OF RAINBOW TROUT Oncorhynchus mykiss IN AQUAPONICSStrauss 3The European Aquaculture Societywebmaster@aquaeas.orgfalseDD/MM/YYYYaaVZHLXMfzTRLzDrHmAi181982


 Faiqa Atique 1,2, * , Heli Juottonen 1, Sami Taipale 1 , Minna Maarit Kytöviita1

 University of Jyväskylä, Finland, Department of Biological and Environmental Science, P.O. Box 35, FIN-40014 University of Jyvaskyla, Finland;


2 Institute of Bioeconomy, JAMK University of Applied Sciences; Tuumalantie 17, 43130 Tarvaala, Finland



 Aquaponics combines  recirculating  aquaculture  (RAS) with hydroponics, a soilless plant farming method . Plant choice in aquaponics may affect the growth  and microbiome of fish because each plant has its specific microbiome, which may alter the microbes in aquaponics. Plant secrete root exudates, which may alter the microbe s in the system. Mint is a plant known for its growth promoter effects on animals, and  it  may influence the fish growth when grown together with fish in aquaponics . On the other hand, fish in aquaponics excrete ammonia, which is toxic to fish and  must be removed from circulating water. Ammonia is  converted to nitrites and then  to nitrates by  microbial action during the  process  of  nitrification. Nitrificati on is an essential process for the performance of RAS and maintains the water quality of aquaponics.  The aims of this study were to investigate  and  the  growth  of fish  and fatty acids contents of rainbow trout (Oncorhynchus mykiss) in aquaponics when grown with mint. The other aims were to investigate microbial communities in the mucous and gut of the rainbow trout and to compare start-up of  nitrification in aquaponics and RAS .

Materials and methods

Seven-week experiment was performed with three replicated RAS and aquaponic systems. Twenty rainbow trout  (initial weight 55 ± 1.06 g )  were stocked in each fish tank for RAS and aquaponic systems. Thirty mint seedlings  were transplanted in each deep water culture rafts . Change in biomass for fish was recorded at the end of  the  experiment. Microbial communities in fish mucous and gut were analysed at the start and end of the experiment. The fatty acids were extracted from fish muscle from the start (fingerlings) and end samples. Concentrations of total ammonia nitrogen, nitrite, nitrate were recorded during the experiment.


The weight gains (aquaponics = 324.33 ± 31.87 g, RAS = 295.13, ± 9.70 g , p = 0.24 ) and specific growth rates (aquaponics = 2.11 ± 0.11 g, RAS = 2.00, ± 0.06 g, p = 0.21) of rainbow trout were similar in RAS and in the aquaponics’. M int  improved the fish growth through reduced feed conversion ratios  (Figure 1).  Mint  reduced the feed consumption of the rainbow trout in aquaponics (Figure 1). However, fish  in aquaponics maintained equal weight as fish reared in RAS despite of the lower feed consumption. The omega 3 fatty acids content  of rainbow trout in aquaponics were slightly higher than the fish reared in RAS but without statistically significant difference. The retention of omega 3  fatty acids content  was speculated in fish because fish maintained fatty acid composition similar to fish in RAS in spite of low feed consumption in aquaponics. M int altered the microbial communities of rainbow trout  in mucous and gut compared to fish reared in RAS.  Nitrification  start-up  was faster in aquaponics than in RAS.


 Aquaponics with mint improved f ish growth, water quality and initiated earlier start-up of nitrification as compared to RAS . Using mint in aquaponics may improve omega 3 fatty acids content of the fish. Growing fish together with mint in aquaponics may lower the feed consumption of fish compared to RAS which will reduce the cost related to fish feed and minimise the impact of aquaculture feed on aquatic environment.

Acknowledgments :  We would like to thank  University of Jyväskylä, JAMK University of Applied Sciences , Sisä-Suomen kalatalousryhmä , Maa- ja Vesitekniikan Tuki Ry and Niemi -säätiö  for their contribution towards this research work. We also thank Juhani Pirhonen for his contribution to this research especially in conceptualizing nitrification process.