Balancing of nutrient uptake by water spinach (Ipomoea aquatica) and mustard green (Brassica juncea) with nutrient production by African catfish (Clarias gariepinus) in scaling aquaponic recirculation system

Abstract

2016): Balancing of nutrient uptake by water spinach (Ipomoea aquatica) and mustard green (Brassica juncea) with nutrient production by African catfish (Clarias gariepinus) in scaling aquaponic recirculation system, Desalination and Water Treatment, A B S T R A C TFrom both engineering and economic perspectives, goals of an aquaponic recirculation system are keeping a healthy environment for fish and plant, by eliminating toxic metabolites and growth-inhibiting substances. The type and quantity of waste excretions produced by the cultured organisms are also the important considerations, especially in designing the component system. Therefore, to be effective at nutrient removal, aquaponic systems should be sized correctly to balance fish output and nutrient uptake by plants. In this study, the plant component was isolated from the fish rearing operation so that nutrient removal could be evaluated independently. Two leafy green vegetables, i.e. water spinach (Ipomoea aquatica) and mustard green (Brassica juncea) were selected to evaluate the effectiveness of plant nutrient uptake to balance nutrient production from fish culture. Results indicated that nitrogen utilization efficiencies of water spinach and mustard green were 66.5 and 59.9%, respectively. In addition, water spinach-based aquaponics had better water quality than that of mustard green-based aquaponics, primarily due to its higher root surface area. The growth performance of African catfish showed the feed conversion ratio was in the range 1.18-1.33. The results obtained from this study indicated that both crops have considerable impacts on nutrient removal.

Effect of stocking density of fish on water quality and growth performance of European Carp and leafy vegetables in a low-tech aquaponic system

“…Fish raised in AP can achieve growth rates comparable to those obtained with recirculating systems of aquaculture [29] and FCR within the range of conventional aquaculture [30]. Differences in species, design of AP systems, water temperature and quality, initial sizes and stocking densities of fish, composition of feed and feeding rates justify different results among studies.…”

Hydroponic horticulture using residual waters fromOreochromis niloticusaquaculture with biofloc technology in photoautotrophic conditions withChlorellamicroalgae

“…In DAPS is possible to manage different environmental conditions in water for both components and is feasible to add complementary nutrients in the hydroponic system, not provided from aquaculture, to satisfy optimal nutritional requirements for the horticulture, according to plant development needs, without any side effects for the aquaculture organisms (Goddek et al., 2016; Goddek & Körner, 2019; Lennard & Goddek, 2019). DAPS is a very promising strategy not only for green leaf horticulture but for other horticulture species given that residuals are comprised of a high amount of nutrients in the form of nitrate, nitrite and ammonium (Endut, Lananan, Abdul Hamid, Jusoh, & Wan Nik, 2016; Graber & Junge, 2009; Masser, Rakocy, & Losordo, 1999), these nutrients can be obtained from the liquid fraction of RAS effluents (Endut, Jusoh, Ali, Wan Nik, & Hassan, 2010), and even though the concentration of dissolved nutrients in aquaculture effluent is lower than in traditional hydroponic nutrient solution (Bittsanszky et al., 2016), complementation of calcium, potassium, phosphorous and iron can be necessary (Monsees, Keitel, Paul, Kloas, & Wuertz, 2017; Rakocy, 2007) which increases the costs (Goddek et al., 2015). Regarding circular economy and the sustainability of the systems, several authors have implemented processes for recovering the solid fraction from aquaculture to mineralizing and using them in aquaponics (Delaide, Goddek, Keesman, & Jijakli, 2018; Delaide, Monsees, Gross, & Goddek, 2019; Goddek et al., 2018; Joesting, Blaylock, Biber, & Ray, 2016; Monsees et al, 2017; da Silva Cerozi, 2016).…”

Role of stocking density of tilapia (Oreochromis aureus) on fish growth, water quality and tomato (Solanum lycopersicum) plant biomass in the aquaponic system

“…FCR as one of the most import parameters in terms of economy of the aquaponic system should optimize in parallel to fish density and feding ratio. Thus, in our case, the minimum FCR was observed in the group [15] and Endut [16] for the aquaponic production. pH values fluctuated in all groups during the present study.…”