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The union of aquaculture and hydroponics is named aquaponics—a system where microorganisms, fish and plants coexist in a water environment. Bacteria are essential in processes which are fundamental for the functioning and equilibrium of aquaponic systems. Such processes are nitrification, extraction of various macro- and micronutrients from the feed leftovers and feces, etc. However, in aquaponics there are not only beneficial, but also potentially hazardous microorganisms of fish, human, and plant origin. It is important to establish the presence of human pathogens, their way of entering the aforementioned systems, and their control in order to assess the risk to human health when consuming plants and fish grown in aquaponics. Literature analysis shows that aquaponic bacteria and yeasts are mainly pathogenic to fish and humans but rarely to plants, while most of the molds are pathogenic to humans, plants, and fish. Since the various human pathogenic bacteria and fungi found in aquaponics enter the water when proper hygiene practices are not applied and followed, if these requirements are met, aquaponic systems are a good choice for growing healthy fish and plants safe for human consumption. However, many of the aquaponic pathogens are listed in the WHO list of drug-resistant bacteria for which new antibiotics are urgently needed, making disease control by antibiotics a real challenge. Because pathogen control by conventional physical methods, chemical methods, and antibiotic treatment is potentially harmful to humans, fish, plants, and beneficial microorganisms, a biological control with antagonistic microorganisms, phytotherapy, bacteriophage therapy, and nanomedicine are potential alternatives to these methods. [ABSTRACT FROM AUTHOR]

Aquaponics represents an alternative to traditional soil cultivation. To solve the problem of nutrient depletion that occurs in this biotechnological system, the application of a spirulina-based biofertilizer was assessed. The microalgal waste used in this study came from industrial processing. Four different dilutions of the supernatant portion of this waste were sprayed on lettuce plants cultivated in an aquaponics system installed at the Botanical Gardens of the Tor Vergata University of Rome. The biofertilizer was characterized to evaluate its amount of macro- and micronutrients. The analysis conducted on the plants involved both morpho-biometric aspects and qualitative–quantitative measurements. The experiments showed that the spirulina extract had a positive effect on the growth and nutraceutical content of the lettuce plants; the obtained results highlighted that a dilution of 75% was the best for treatment. The use of the proposed organic and recycled fertilizer could increase the sustainability of crop cultivation and promote the functioning of aquaponics systems. [ABSTRACT FROM AUTHOR]

Water quality is an important factor in the process of fish farming. This study aims to determine the application of FBs pressure that can increase the productivity of comet goldfish Carassius auratus farming in an aquaponic system. The research was carried out from January to March 2022 at the Ciparanje Green House, Faculty of Fisheries and Marine Sciences, Padjadjaran University, Jatinangor. This study used a completely randomized design (CRD) experimental method with four treatments and three replications. The treatment used was the application of FBs pressure of 0 atm (A), 5.25 atm (B), 5.5 atm (C), and 5.75 atm (D). Maintenance of test fish for 30 days with ad satiation feeding. Observation of fish growth through sampling is done by taking fish 10% of the total population randomly in each pond. Data were analyzed using the F test at a 95% confidence level, followed by Duncan's multiple range test with a 95% confidence level, while water quality data were analyzed descriptively. The results showed that the specific daily growth rate of FBs 5.75 was 2.51%, the absolute length growth was 3.33%, the absolute weight growth was 1.70 g and the fish survival rate was 99.3%. It was concluded that the use of FBs in the aquaponic system can increase production of the system. [ABSTRACT FROM AUTHOR]

Aquaponic production system, which creates a sustainable production ecosystem by bringing water, fish, and plants together in a closed system, is a reflection of sustainable economic activities in aquaculture. In this context, the aim of the study was to investigate the cultivation possibilities of carp, lavender, and basil in two different grow beds (water and mollusc shell) created in the aquaponic production system. Basil and lavender as plant material and carp as fish material were used in the study. The experimental design was formed from 12 pots of 90 L volume, and the experiment was continued for 60 days with 3 replications. In the study, reasonably high values for specific growth rate (1.96±0.01 g), condition factor (1.5), and survival rate (97.05%) were obtained in carp. While basil (23.5 cm, 23.5 cm, and 16.5 cm) and lavender (16.57 cm, 15.14 cm end 9.73 cm) grown in water media performed better in terms of plant height, root length, and dry herb yield, the green herb yields of basil (49 cm) and Levander (19 cm) were found to be high for both plants in the mollusc shell media. The maximum NH4, NO3+NO2, and PO4 values were determined as 1.30 mg L-1 (in 3. quarter and fish tank), 40.07 mg/L (in 3. quarter and Levander shell group), and 0.37 mg L-1 (in 1. quarter and basil shell group) respectively. [ABSTRACT FROM AUTHOR]

Crops grown on aquaponics farms are susceptible to various diseases or biotic stresses during their growth cycle, just like traditional agriculture. The early detection of diseases is crucial to witnessing the efficiency and progress of the aquaponics system. Aquaponics combines recirculating aquaculture and soilless hydroponics methods and promises to ensure food security, reduce water scarcity, and eliminate carbon footprint. For the large-scale implementation of this farming technique, a unified system is needed that can detect crop diseases and support researchers and farmers in identifying potential causes and treatments at early stages. This study proposes an automatic crop diagnostic system for detecting biotic stresses and managing diseases in four leafy green crops, lettuce, basil, spinach, and parsley, grown in an aquaponics facility. First, a dataset comprising 2640 images is constructed. Then, a disease detection system is developed that works in three phases. The first phase is a crop classification system that identifies the type of crop. The second phase is a disease identification system that determines the crop's health status. The final phase is a disease detection system that localizes and detects the diseased and healthy spots in leaves and categorizes the disease. The proposed approach has shown promising results with accuracy in each of the three phases, reaching 95.83%, 94.13%, and 82.13%, respectively. The final disease detection system is then integrated with an ontology model through a cloud-based application. This ontology model contains domain knowledge related to crop pathology, particularly causes and treatments of different diseases of the studied leafy green crops, which can be automatically extracted upon disease detection allowing agricultural practitioners to take precautionary measures. The proposed application finds its significance as a decision support system that can automate aquaponics facility health monitoring and assist agricultural practitioners in decision-making processes regarding crop and disease management. [ABSTRACT FROM AUTHOR]

The recycling processes of aquaponic waste into fertilizers are highly dependent on the type and activity of nitrifying bacteria in the system. This study aims to find indigenous nitrifiers to enhance nutrient recovery in an aquaponics system. Twelve indigenous nitrifiers consisting of ammonia and nitrite‐degrading bacteria were isolated from a local earthen pond of Nile tilapia (Oreochromis niloticus), and two isolates (AQ4 and AQ12) were selected due to their highest capacity to degrade either ammonia or nitrate respectively. Based on the 16S rRNA gene sequences, these isolates were identified as Marinobacter nauticus (AQ4) with 98.64% similarity, and Bacillus sp. (AQ12) with 99.89% similarity. When these bacterial isolates were applied in aquaponics systems with bacterial enhancement (aquaponicsBE), the nutrient recovery was significantly higher compared to the control (aquaponicsctrl), indicated by a 500 g higher total harvested biomass. With a significance value of p < 0.05, aquaponicsBE gives 17% higher crude fat and protein retention in vegetables while in fish 14% higher crude fat was found. Energy retention in vegetables was 23% higher than in the control. Furthermore, fish grew better in the aquaponicsBE system, with 0.6%BW/day higher specific growth rate, and 0.05 better feed conversion ratio compared to that of fish reared in the control. [ABSTRACT FROM AUTHOR]

Purpose: Substitution of animal-source foods with plant-based alternatives requires product-specific information from both the environmental and nutritional perspectives. The use of nutrient indices as nutritional functional units (nFUs) in Life Cycle Assessment (LCA) of food products has been developed to integrate nutritional aspects into the method (nLCA). However, the methodological approaches vary because the execution of LCA always depends on context. Methods: We present a methodological approach for the nLCA of protein-rich foods with a product-group-specific nFU, as update to earlier development work. We compared three strategies for selecting nutrients to be included in the nFU index for protein-rich foods in a national context, considering Finnish nutrition recommendations to different age groups, and the population's dietary habits and nutrient intake. nFUs were demonstrated through cradle-to-plate LCA for foods made with beef, pork, broiler, trout, perch, chickpea, soya mince, and pulled oats as the main ingredients. Results: The selected strategies to format the nFU have a marked impact on the results especially for fish- and plant-based food. The results of each population group, especially children, also differ. The choice of nutrients in the index, the type of food assessed, and the system boundaries of assessment have a considerable impact on the results. Conclusion: The baseline nFU introduced in the study is valuable in producing sustainability information to support the aspiration to a sustainable dietary shift. The index used as the nFU should be formatted based on the study goal and scope, and vulnerable groups must be considered when interpreting the results. [ABSTRACT FROM AUTHOR]

As nutrient-rich water in aquaponic systems cannot supply growing plants with all the required trace elements, supplementation with specific fertilizers is performed to make up for this deficit. While chelated fertilizers such as ethylenediaminetetraacetic acid–zinc disodium complex (Zn-EDTA) are becoming more popular in this context for improving plant growth in aquaponic systems, little is known about their effects on fish. During two experiments, a total of 576 individuals of catfish fry (0.19 g) and fingerlings (220.01 g) of the African catfish (Clarias gariepinus; Burchell, 1822) were kept separately for 32 days under experimental aquarium conditions. The fry was exposed to 0.125 and 0.5 mg/L, while the fingerlings were exposed to 0.5 and 2.0 mg/L Zn-EDTA in a plantless aquaponic system. The third treatment group consisted of a control group without Zn-EDTA. The growth, mortality, and ethological indicators were assessed for all growth stages, while the leukocyte distribution and histopathological changes were additionally determined for the fingerlings. As the feed intake in the experiment was limited, the investigations were focused on the effects of Zn-EDTA and not on the growth process of a respective fish growth stage. While the growth, mortality, and behavior were not significantly different in both growing stages, the number of mature neutrophils changed significantly in all treatments in fingerlings. Zn was not detected in the histologically investigated organs at the tested concentrations using the staining method. However, morphological alterations of the gill epithelium were found on the secondary lamellae. Quantitative multiplex PCR was used to simultaneously evaluate the expression of 17 genes related to Zn metabolism and stress physiology in head kidney samples. The transcripts of several selected genes changed by up to 70-fold. Due to high individual variances, only the copy numbers of the KMT2A (lysine-specific methyltransferase 2a) gene were significantly different across treatment groups and sampling points. However, the present results indicate that the addition of Zn-EDTA at the tested concentrations can be considered relatively benign for the health and welfare of C. gariepinus, as no toxic effects of Zn-EDTA were observed in moderately hard to hard water.

Abstract This research aimed to standardize the growth of two commonly cultivated herbs in the United Arab Emirates, basil (Ocimum basilicum L.) and coriander (Coriandrum sativum L.), within an aquaponic system. The study compared a recirculatory aquaponic system (RAS) with static aquaculture systems (for fish performance) and irrigated greenhouse cultivation systems (for herb performance). The project assessed growth, element composition, and aquaponic efficacy to determine the viability of aquaponics for these herbs. In the soilless (aquaponic) system, both herbs exhibited significantly enhanced growth parameters, including plant height, root length, leaf count, and fresh and dry weights, compared to conventional soil‐based cultivation. This growth enhancement was attributed to the additional nutrients derived from fish waste in the aquaponic system. Furthermore, plants displayed significantly higher element levels, highlighting the effectiveness of aquaponics in nutrient delivery. Notably, the aquaponic system demonstrated superior antioxidant activity in both herbs. The study also revealed remarkable water use efficiency in the aquaponic system, with water savings exceeding 90% compared to conventional methods. These findings establish the efficiency and sustainability of aquaponic systems over traditional food production approaches, particularly in arid regions such as the United Arab Emirates. Utilizing an aquaponic system for these commonly cultivated herbs resulted in improved growth and resource efficiency, affirming its viability as an environmentally sustainable and efficient method of food production in desert climates.

Background: Aquaponics and hydroponics are potential alternative techniques for sustainable cultivating of medicinal plants. Setting: The experiments were carried out on the Bellville campus of the Cape Peninsula University of Technology, Cape Town, South Africa. Aim: The aim of this study was to evaluate crop yield, secondary metabolite contents, and the antifungal activities of extracts from Helichrysum cymosum (H. cymosum) grown in aquaponic and hydroponic systems compared with field-collected plants. Methods: Helichrysum cymosum seedlings were cultivated in hydroponic and aquaponic systems for 6 weeks under greenhouse conditions. The data on plant growth parameters, phytochemical analyses of the leaves, anti-Fusarium oxysporum (F. oxysporum) activity of ethanolic extracts, and antioxidant capacities were recorded. Results: The results showed that the heights of plants grown in aquaponics and hydroponics did not differ substantially (p 0.05). The total polyphenol contents varied significantly (p 0.01) among the three cultivation techniques, with the field-collected plants yielding the highest contents (452.10 mg GAE/g ± 53.37 mg GAE/g). The flavonol contents differed significantly among the three cultivation techniques (p 0.05), with the highest flavonol contents in the field-collected plants (250.62 mg QE/g ± 58.12 mg QE/g). The plants grown in aquaponics had the highest number of compounds (104). The microdilution bioassay showed that the ethanolic extracts of field-harvested H. cymosum had higher fungistatic activity against F. oxysporum. The highest antioxidant capacity was recorded in 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay for plants cultivated in hydroponics (p 0.05), while field-collected plants showed a significantly higher value of 2719.42 µmol ± 278.72 µmol AAE/g (p 0.05) in the ferric ion reducing antioxidant parameter (FRAP) assay. Conclusion: The field-collected plants performed better in phytochemical contents. However, cultivation of H. cymosum using a hydroponic system may be feasible based on the antioxidant results. Contributions: The study contributes to developing an alternative strategy for cultivating plants and promoting sustainable farming.

The depletion of natural resources such as freshwater and cropland makes it necessary to find a new solution for sustainable food production. Aquaponic systems seem to be a great alternative to traditional agriculture, however, there are still many unknowns that need to be explored. It is already known how fish stocking affects water quality in aquaponic systems, but not how it affects the plants’ growth, and especially on chlorophyll fluorescence. In this study, we examined how the density of 0, 2, 4, 8, and 16 stocking fish in five aquaria affects lettuce growth. The first tank was only a hydroponic system with plants but without fish (control). In the remaining four aquaria – 2, 4, 8 and 12 specimens of common carp fry with an average weight of 20 grams (average 8.5–33.2 g) were placed in the aquaponic growing system. Physicochemical analysis of water was conducted to determine the levels of pH, electrical conductivity ( EC), N-NO 3, N-NO 2, N-NH 4, P-PO 4, O 2 and physiological parameters of plants (nitrogen balance index – NBI, chlorophyll content index – CCI, quantum yield – QY, flavonoid content – Flv) were analysed. The results showed that fish stocking density has different effects on plant physiological parameters, but in most cases, was insignificant. It seems that the greater number of fishes and higher density indirectly causes growth inhibition (lower photosynthetic efficiency) due to the increase of N-NO 3 and a decrease of O 2 in the water.

Deep learning and computer vision techniques have gained significant attention in the agriculture sector due to their non-destructive and contactless features. These techniques are also being integrated into modern farming systems, such as aquaponics, to address the challenges hindering its commercialization and large-scale implementation. Aquaponics is a farming technology that combines a recirculating aquaculture system and soilless hydroponics agriculture, that promises to address food security issues. To complement the current research efforts, a methodology is proposed to automatically measure the morphological traits of crops such as width, length and area and estimate the effective plant spacing between grow channels. Plant spacing is one of the key design parameters that are dependent on crop type and its morphological traits and hence needs to be monitored to ensure high crop yield and quality which can be impacted due to foliage occlusion or overlapping as the crop grows. The proposed approach uses Mask-RCNN to estimate the size of the crops and a mathematical model to determine plant spacing for a self-adaptive aquaponics farm. For common little gem romaine lettuce, the growth is estimated within 2 cm of error for both length and width. The final model is deployed on a cloud-based application and integrated with an ontology model containing domain knowledge of the aquaponics system. The relevant knowledge about crop characteristics and optimal plant spacing is extracted from ontology and compared with results obtained from the final model to suggest further actions. The proposed application finds its significance as a decision support system that can pave the way for intelligent system monitoring and control.

In aquaponic farming, there is a potential risk that heavy metals will contaminate the water, which can lead to heavy metal accumulation in the plants. Our research investigated the accumulation of mercury (Hg) and lead (Pb) under aquaponic conditions and the effect of their increased presence on the uptake of other macro- and micronutrients using watercress (Nasturtium officinale) as a model plant. The potential modifying effect of humic acid on heavy metal accumulation was also investigated. Adding Hg and Pb increased the mercury and lead levels of the watercress plants to over 300 µg kg−1, while the addition of humic acid significantly reduced the concentration of both mercury and lead in the plants compared to plants treated with heavy metals alone, from 310.647 µg kg−1 to 196.320 µg kg−1 for Hg and from 313.962 µg kg−1 to 203.508 µg kg−1 for Pb. For Fe and Mn, higher values were obtained for the Hg + humic acid treatments (188.13 mg kg−1 and 6423.92 µg kg−1, respectively) and for the Pb + humic acid treatments (198.26 mg kg−1 and 6454.31 µg kg−1, respectively). Conversely, the Na, K, Cu levels were lower compared to those in plants treated with heavy metals alone. Our results demonstrated that watercress can accumulate mercury, leading to high levels, even above food safety standards, highlighting the importance of water quality control in aquaponic systems. Furthermore, these results suggest that watercress could be used as a natural filter in recirculation systems. The addition of humic acid significantly reduced the accumulation of heavy metals and altered the element content in the plant.

The increasing population, its requirements for food, and the environmental impact of the excessive use of inputs make crop production a pressing challenge. Integrated nutrient management (INM) has emerged as a critical solution by maximizing nutrient availability and utilization for crops and vegetables. This review paper highlights the potential benefits of INM for various vegetables and field crops and explores the conceptual strategies, components, and principles underlying this approach. Studies have shown that a wide range of vegetables and field crops benefit from INM, in terms of increased yield and improvements in yield attributes, nutrient contents and uptake, growth parameters, and various physiological and biochemical characteristics. This paper discusses biostimulants, their categories, and their impact on plant propagation, growth, photosynthesis, seed germination, fruit set, and quality. Additionally, this review explores modern sustainable soilless production techniques such as hydroponics, aeroponics, and aquaponics. These cultivation methods highlight the advancements of controlled-environment agriculture (CEA) and its contribution to nutrient management, food security and minimizing the environmental footprint. The review concludes by proposing methods and fostering discussions on INM’s future development, while acknowledging the challenges associated with its adoption. Finally, this review emphasizes the substantial evidence supporting INM as a novel and ecologically sound strategy for achieving sustainable agricultural production worldwide.

The increase in the unemployment rate in Bojong Pandan Village after the Covid-19 pandemic has threatened the stability of family food security. This condition threatens to make families in Bojong Pandan Village experience difficulties in meeting their basic needs through food. Budikdamber innovation is a solution to maintain family food security stability. However, the community still needs to gain knowledge and skills regarding Budikdamber, so there is a need for synergy between the village government and universities through community service activities. This service aims to increase the participant's knowledge and skills regarding Budikdamber. Implementation methods to support the achievement of the goals of this service include surveys, preparation, implementation, and evaluation. The results obtained from this community service activity were an increase in the participants' knowledge of 47.47%, and all participants could practice the tutorial activities for making Budikdamber. Follow-up of this activity will be routine monitoring at least once a month and innovating variations on fish and plant species other than catfish and water spinach.

The effects of prolonged photoperiod (additional night lighting) were investigated on the production of Ocimum basilicum (lemon basil) and fish/crayfish raised in a nutrient film technique aquaponic system. Hybrid lemon fin barb and red claw crayfish juveniles were co-cultured with O. basilicum and subjected to 12 h of ambient natural daylight and additional 0, 4, 8, and 12 h of night lighting for 14 weeks (two batches of 7 weeks each). The water quality parameters and the performance characteristics of the fish/crayfish/plant were evaluated, and the nutrient uptake (nitrogen, phosphorus, and potassium) in the system by the three organisms was also measured. The fish growth performance showed no significant differences (p > 0.05) in all the growth parameters measured across the treatments. The body proximate and nitrogen, phosphate, and potassium (NPK) composition of the fish and crayfish were not significantly (p > 0.05) different across the treatments. Similarly, there was no significant difference (p > 0.05) in the NPK uptake by the fish and crayfish across the treatments. The plant growth performance showed that there were no significant (p > 0.05) differences in the plant growth parameters measured, except for % plant height gained in the 12 h-light treatment (403.2 ± 26.0%) which was significantly (p < 0.05) higher than other treatments and cycles. Hence, this study demonstrated that varying supplementary night lighting has no significant effect on the growth performance of O. basilicum, hybrid lemon fin barb, and red claw crayfish. This study, therefore, suggests that supplementary night lighting should not be considered for O. basilicum production as it does not significantly improve the performance characteristics of the plant nor the fish co-cultured with it in a polyculture aquaponic system.

The paper discusses the current prognoses of aquaculture development worldwide putting an emphasis on its effect on the environment and the issue of the protection of water reservoirs in different countries. Water consumption in diversified aquaculture systems is presented herein as well as the characteristics of the mechanical and biological water treatment methods in fish farms, with particular attention paid to the recirculating water systems. New aquaculture technologies using post-production waters are presented. The paper provides a discussion on the contribution of aquaculture to the global greenhouse gas emissions and the means of limiting this emission. The effect of climate change on aquatic ecosystems is presented in the context of the changes of the aquaculture production profile. The paper includes a brief presentation of the methods of mitigating the changes with respect to contamination of aquatic ecosystems as well as climate change. Reducing the water footprint can be achieved through selective breeding, species diversification and implementation of more technologically advanced aquaculture systems such as: integrated multi-trophic aquaculture, aquaponics and recirculation systems in aquaculture. The need for certification of fish farms with water recirculation systems is justified in the paper. The issues addressed herein are summarised and the main areas for extending the research promoting preservation of aquatic ecosystems in aquaculture are presented.

Aquaponics is an integrated form of multi-commodity production system that combines a recirculating aquaculture system with the hydroponic cultivation of crops using the same water via recirculation using pumps. However, the ideal density of cultured aquatic species and the suitable fish/plants/fish feed combinations applicable under aquaponics must be established to determine its impact on the system's performance, including the local growing conditions that could affect its productivity. Eighteen aquaponic systems following a closed-loop water recirculation method were established for the production of red tilapia, giant river prawns, lettuce, and duckweed. The study aimed to establish the local growing conditions, water quality, and productivity of the system subjected to different stocking densities of fish (RT24 - 24 fish/m3, and RT48 - 48 fish/m3) and prawn (P0 – zero prawn, P12 - 12 prawns/m2, and P25 - 25 prawns/m2. Results show that with an ambient air temperature and humidity ranging from 30 – 35°C and 52 – 71% during the production, the obtained water quality conditions in the system were: water temperature 27 – 30°C; dissolved oxygen (DO) 2.8 – 3.3 mg/L; pH – 8.3; total ammonia nitrogen (TAN) close to 0, Nitrite – 0; Nitrate – 40 to 160 mg/L; total dissolved solids (TDS) – 580 mg/L; and a daily water loss of 1.47% which were within the tolerable growth conditions of the different species. The stocking density of 24 fish/m3 and 12 prawns/m2 resulted in better growth and yield performance of the cultured aquatic species. However, the stocking densities had no significant effect on the growth and yield of lettuce and duckweed.

Purpose Aquaponics combine aquaculture with crop production in a mutual system. In this experiment, the growth of Amaranthus in aquaponics with tilapia fish was investigated. Method 500-liter water tanks containing tilapia fish at four initial stocking densities of 100, 150, 200, and 250 fish/m3 were used in triplicates, with a view to evaluate vegetable yields as influenced by fish biomass to water ratio. 1 g of Amaranthus seeds were sown in a 1 m2 planting trough, which contained gravel with a top layer of sandy soil. The pots were flooded with water from fish holdings by an aquarium pump. Results The germination rate of Amaranthus was not significantly different across the experimental setup (Pâ>â0.05). The growth rate of Amaranthus was significantly higher with increasing fish density (Pâ

Aquaponics offers a soilless farming ecosystem by merging modern hydroponics with aquaculture. The fish food is provided to the aquaculture, and the ammonia generated by the fish is converted to nitrate using specialized bacteria, which is an essential resource for vegetation. Fluctuations in the ammonia levels affect the generated nitrate levels and influence farm yields. The sensor-based autonomous control of aquaponics can offer a highly rewarding solution, which can enable much more efficient ecosystems. Also, manual control of the whole aquaponics operation is prone to human error. Artificial Intelligence-powered Internet of Things solutions can reduce human intervention to a certain extent, realizing more scalable environments to handle the food production problem. In this research, an attention-based Temporal Fusion Transformers deep learning model was proposed and validated to forecast nitrate levels in an aquaponics environment. An aquaponics dataset with temporal features and a high number of input lines has been employed for validation and extensive analysis. Experimental results demonstrate significant improvements of the proposed model over baseline models in terms of MAE, MSE, and Explained Variance metrics considering one-hour sequences. Utilizing the proposed solution can help enhance the automation of aquaponics environments. [ABSTRACT FROM AUTHOR]

Stocking density is a key factor affecting the health of aquatic organisms in industrial aquaponics. In this study, Micropterus salmoides were assigned to one of two density groups (160 and 120 fish/m3) for 40 days. The growth performance, intestinal morphology, enzyme activity, and microbial communities were compared between the two density groups. The findings revealed that the higher stocking density condition exhibited an increased weight gain rate and specific growth rate during the developmental phase of the juvenile M. salmoides. Moreover, remarkable increases in villi height, villi width, and muscular layer thickness were observed. Additionally, this elevated stocking density condition also enhanced the activity of intestinal antioxidant enzymes, consequently improving the structural integrity of the intestine and augmenting the digestive and absorptive capacities of the juvenile M. salmoides. With regard to the intestinal microbial community, the dominant phyla detected were Firmicutes and Proteobacteria. However, under the higher stocking density condition, there was a significant upsurge in the abundance of Mycoplasma. Consequently, it is advised to mitigate the abundance of such pathogenic microorganisms through the regulation of the water environment during the aquacultural process. Drawing from recent investigations on the impact of various factors on the intestinal microbiota of M. salmoides, it can be deduced that the composition of the intestinal microbiota is closely intertwined with factors including aquaculture practices, feed composition, water environment, and developmental stage. In summary, the aforementioned research findings possess noteworthy implications for the control of stocking density in the cultivation of juvenile M. salmoides. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fish sludge solubilization and phototrophic bioconversion is tested in aquaponics. • Anaerobic solubilization is superior to aerobic one in providing volatile fatty acids. • Phototrophic bioconversion is conducted using purple phototrophic bacteria. • Light-anaerobic condition achieves the desired biomass and mineral nutrients. • A novel multiloop aquaponics is proposed for the reuse of phototrophic nutrients. Nutrient recovery from fish sludge in aquaponics is crucial to improve the economic output of a system sustainably and hygienically. Currently, fish sludge is treated using conventional anaerobic and aerobic mineralization, which does not allow the recovery of valuable nutrients in fish wastes. In this study, a two-stage approach (named as solubilization process and phototrophic bioconversion) is proposed to convert fish sludge into mineral nutrients and biomass nutrients using purple phototrophic bacteria (PPB), thereby promoting the growth of plants and fish simultaneously in aquaponics. Anaerobic and aerobic solubilization methods are tested to pretreat the fish sludge, generating substrates for PPB. Anaerobic solubilization yields 2.1 times more soluble chemical oxygen demand (SCOD) and 3.7 times more total volatile fatty acid (t-VFA) from fish sludge compared with aerobic solubilization. The anaerobic solubilization effluent indicates a COD t-VFA /SCOD of 60% and a VFA comprising 13.3% acetate and 49.0% propionate for PPB. The phototrophic bioconversion using anaerobic solubilization effluent under the light-anaerobic condition results in the highest biomass yield (0.94 g COD biomass /g COD removed) and the highest PPB dominance (Ectothiorhodospira , 58.7%). The anaerobic solubilization and light-anaerobic phototrophic bioconversion achieves 54.1% of carbon recovery efficiency (CRE) (in terms of COD), as well as 44.8% and 91.3% of nutrient recovery efficiency (NRE) for N and P. A novel multiloop aquaponic system combined with PPB-based nutrient recovery is proposed for the reuse of mineral nutrients and PPB biomass generated from fish sludge. [ABSTRACT FROM AUTHOR]

The Nutrient Film Technique (NFT) in aquaponics is a closed aquaculture system favored by Indonesian aquaculturists due to its environmental friendliness and can be applied on a small scale. Climbing perch (Anabas testudineus) has the potential to be cultured in this system as small-scale livestock. This research aims to determine the performance of the NFT aquaponics system of Anabas testudineus and Brassica chinensis with different stock densities. A completely randomized design within four stock density treatments and five replications was applied to this study. The results showed that the specific growth rate, survival rate, and feed conversion rate (FCR) of A. testudineus differed significantly across treatments (p < 0.05). The best performance of specific growth rate (1.96 ± 0.15%), FCR (1.31 ± 0.13), and survival rate (88 ± 4.69%) were shown in the second treatment (50 fish/tank). On the other hand, the fourth treatment (100 fish/tank) yielded the tallest B. chinensis at 20.7 ± 0.90 cm and a leaf number of 10.68 ± 0.28. Higher fish stocking density resulted in a slower fish growth rate but a faster plant growth rate. It can be concluded that the aquaponics system of NFT with a density of 50 fish/tank could be applied to small-scale livestock. The amount of organic matter that plant roots can use as nutrients is the factor that determines the growth rate of B. chinensis. [ABSTRACT FROM AUTHOR]

Aquaponics with bio-floc can potentially offer sustainable food production with zero waste as it allows farming plants and fish simultaneously, whereby the former use fish waste as their nutrient sources, while the latter receives cleaner water from the plants in a closedloop system. In the aquaponics system, additional nutrients are usually added to support optimal plant growth, but it is suggested that the amount of such chemical nutrients should be controlled to prevent any harm to the fish. Furthermore, the plant and fish growth rates are influenced by the nutrients and the culture media used. This study aims to examine the effect of nutrition (full-nutrient and half-nutrient treatments) and different types of culture mediums (rockwool, rockwool-perlite, and rockwool-husk) on the growth rates of pak choi (Brassica rapa) and catfish (Clarias gariepinus) using split-plot design. Findings show that the half-nutrient treatment yielded a 17.12% higher plant growth rate and 23.87% heavier catfish weight than the full-nutrient treatment, but these treatments did not affect the fish survival rate. It was also observed that using different culture mediums did not result in any significant difference. [ABSTRACT FROM AUTHOR]

‘Cherokee Purple’ tomato (Solanum lycopersicum L.) plants are a highly sought-after heirloom cultivar in the United States but are low yielding and highly susceptible to soil-borne pathogens, and may benefit from being grafted. Soilless systems such as aquaponics and hydroponics help increase yield, mitigate disease, and serve as an alternative to field production. The objective of this study was to evaluate a grafting combination of ‘Cherokee Purple’ × ‘Maxifort’ and nongrafted controls in 1.85-m² media grow beds with hydroponic and aquaponic systems using copper nose bluegill in a greenhouse. Grafting increased stem diameter, leaf count, stem height, flower count, and bud count compared with nongrafted plants. In aquaponics, grafting increased the phosphorus uptake over nongrafted plants grown in the aquaponic system. Grafting resulted in greater fresh (49.2%) and dry (40.0%) shoot biomass, and fresh (33.3%) and dry (42.8%) root biomass. Grafting also increased the uptake of copper and sulfur in the aquaponic systems. The hydroponic systems resulted in greater leaf count, soil plant analysis development, stem height, shoot biomass, and greater boron, phosphorus, potassium, iron, and manganese levels than aquaponic systems. Total fruit number and weight were greater in hydroponic systems than in aquaponic systems by 35.4% and 30.4%, respectively, but fruit splitting was a problem in both. Aquaponics resulted in greater root fresh weight than hydroponics. The nutrients zinc and copper increased with the use of aquaponic systems over hydroponic systems. This research suggests that the type of system can affect growth and nutrient uptake, and ‘Cherokee Purple’ should not be used in a soilless system because of excessive fruit splitting, leading to unmarketable fruit and low yield, unless environmental conditions can be managed during the heat of the summer. [ABSTRACT FROM AUTHOR]

Aquaponic systems, an integration of aquaculture and hydroponics, have untapped potential due to challenges in water quality control, nutrient deficiency detection, feed management, and the lack of comprehensive market feasibility analysis. This study introduces an innovative approach that employs sensor technology, internet of things and machine learning to effectively address these issues. The Internet of things system is developed to monitor status of water and A Neural Network training model is developed to predict water quality parameters proactively before they reach critical levels, optimizing system efficiency, yield, and sustainability. By applying a deep learning-based model, nutrient deficiencies are detected early, using a convolutional neural network that classifies crops based on nutrient content. This gap-filling measure provides valuable insights for nutrient management in aquaponic systems. A novel automated fish-feeding mechanism, leveraging machine learning, eliminates the drawbacks of manual control and enhances system performance, product quality, and profitability. Additionally, a market feasibility analysis model, absent in prior systems, helps to forecast, and reduce the risk of overselling or unsold products. These advancements contribute significantly to the commercial and sustainable potential of aquaponic farming, providing a robust framework for future research and development. [ABSTRACT FROM AUTHOR]

Aquaponics is an emerging area of agricultural sciences that combines aquaculture and hydroponics in a symbiotic way to enhance crop production. A stable smart aquaponic system requires estimating the fish size in real time. Though deep learning has shown promise in the context of smart aquaponics, most smart systems are extremely slow and costly and cannot be deployed on a large scale. Therefore, we design and present a novel neuromorphic computer that uses spiking neural networks (SNNs) for estimating not only the length but also the weight of the fish. To train the SNN, we present a novel hybrid scheme in which some of the neural layers are trained using direct SNN backpropagation, while others are trained using standard backpropagation. By doing this, a blend of high hardware efficiency and accuracy can be achieved. The proposed computer SpikoPoniC can classify more than 84 million fish samples in a second, achieving a speedup of at least 3369× over traditional general-purpose computers. The SpikoPoniC consumes less than 1100 slice registers on Virtex 6 and is much cheaper than most SNN-based hardware systems. To the best of our knowledge, this is the first SNN-based neuromorphic system that performs smart real-time aquaponic monitoring. [ABSTRACT FROM AUTHOR]

Aquaponics is the combined culture of fish and plants in recirculating aquaculture systems, considered to be an innovative, eco-friendly and sustainable technology. The effect of the hydraulic loading rate (HLR) on the performance of fish and plants in the aquapoinc system was the main aim of this study. Four hydraulic loading rates were applied, 1.2, 1.8, 2.4 and 3.0 m day−1 under stocking density tilapia fish of 5 kg m−3 and lettuce population of 25 plant m−2 for a period of January to March, 2023. Water parameters, plant and fish parameters were determined. The most important results revealed that the highest plant nutrients removal was at HLR of 2.4 m day−1. The highest value of water parameters were found at the HLR of 2.4 m day−1. Root length increased with increasing HLR. Fresh and dry shoot and root weight values were higher at 2.4 m day−1 compared to other treatments under study. Meanwhile, fish growth parameter showed higher values at the HLR of 3.0 m day−1 compared to other treatments. The highest values of weight gain, feed growth rate, specific growth rate and feed conversion ratio were 81.72 g, 1.36 g day−1, 1.88% day−1 and 1.20 g feed g−1 fish, respectively, for all treatments under study. [ABSTRACT FROM AUTHOR]

The Mediterranean region is highly vulnerable to climate change, soil and water resource degradation, and biodiversity loss. These challenges disproportionately affect disadvantaged rural areas, impacting both natural resources and the livelihoods of local agricultural societies. Urgent transformative measures are essential to address land and water management as well as food security challenges in these disadvantaged areas. Living labs are being called upon to play a key role in addressing these challenges through the development of Nature-based Solutions (NbSs) that are able to provide environmental and socioeconomic benefits towards the achievement of Sustainable Development Goals. The aim of this work is to provide insights on an open innovation ecosystem of Mediterranean Living Labs for the synergetic development and participatory assessment of decentralized wetland-aquaponics, as NbSs are able to address environmental and food security challenges in disadvantaged rural areas. The study addresses the knowledge gap of Living Labs contribution to the development of decentralized wetland-aquaponics and the limited research on small-scale aquaponics systems in rural Mediterranean settings, while revealing the role of public participation in ascertaining the solution and evaluating its feasibility and impacts in light of the local social values and interests in the mountainous area of Akkar al-Atika in Lebanon. [ABSTRACT FROM AUTHOR]

The slow growth rate of empurau (Tor tambroides) fish has been reported, impeding its aquaculture practice extensively in Malaysia. It mainly occurs at the fry to fingerling phase. Hence, the present research evaluated the dietary lacto-sacc feed supplement on the growth performance and health status of T. tambroides fries. The fish growth was outperformed significantly (P < 0.05) after 12 weeks in fish fed with the lacto-sacc supplemented fish feed compared to the nonsupplemented control diet. As with the growth performance, the basic hematological parameters were significantly (P < 0.05) improved. This study was the first attempt to indicate the suitability of dietary lacto-sacc for empurau fries nursery in an aquaponics system. Although this study was performed in four types of aquaponics systems, the factorial analysis confirmed that diet had a strong effect for this occurrence. [ABSTRACT FROM AUTHOR]

Today the sustainability of agricultural production systems is widely recognized as a crucial point for the implementation of long-term economically, ecologically sound and socially acceptable policies and practices. This study investigates the role of the public and private partnership (PPP) in the resolution of problems related to the sustainability of both agricultural processes and food production through the integration of the enabling technologies of Industry 4.0 (IoT, Big Data, AI, etc...). In order to better understand how public-private collaboration influences sustainability and digitisation processes in the primary sector, an analysis of what the literature has identified on the topic was conducted and then an attempt was made to answer the research question posed. Through the case study methodology, the research analyses and promotes the results of the ISEPA project. A research project whose PPP had the joint objective of experimenting with new techniques and integrating modern digital technologies in order to foster the sustainability of farming processes, and in particular to promote the advancement of aquaponics systems by also increasing knowledge of their automation. [ABSTRACT FROM AUTHOR]

Biofloc technology is a rearing technique that maintains desired water quality by manipulating carbon and nitrogen and their inherent mixture of organic matter and microbes. Beneficial microorganisms in biofloc systems produce bioactive metabolites that may deter the growth of pathogenic microbes. As little is known about the interaction of biofloc systems and the addition of probiotics, this study focused on this integration to manipulate the microbial community and its interactions within biofloc systems. The present study evaluated two probiotics (B. velezensis AP193 and BiOWiSH FeedBuilder Syn 3) for use in Nile tilapia (Oreochromis niloticus) culture in a biofloc system. Nine independent 3785 L circular tanks were stocked with 120 juveniles (71.4 ± 4.4 g). Tilapia were fed for 16 weeks and randomly assigned three diets: a commercial control diet or a commercial diet top‐coated with either AP193 or BiOWiSH FeedBuilder Syn3. At 14 weeks, the fish were challenged with a low dose of Streptococcus iniae (ARS‐98‐60, 7.2 × 107 CFU mL−1, via intraperitoneal injection) in a common garden experimental design. At 16 weeks, the fish were challenged with a high dose of S. iniae (6.6 × 108 CFU mL−1) in the same manner. At the end of each challenge trial, cumulative per cent mortality, lysozyme activity and expression of 4 genes (il‐1β, il6, il8 and tnfα) from the spleen were measured. In both challenges, the mortalities of the probiotic‐fed groups were significantly lower (p <.05) than in the control diet. Although there were some strong trends, probiotic applications did not result in significant immune gene expression changes related to diet during the pre‐trial period and following exposure to S. iniae. Nonetheless, overall il6 expression was lower in fish challenged with a high dose of ARS‐98‐60, while tnfα expression was lower in fish subjected to a lower pathogen dose. Study findings demonstrate the applicability of probiotics as a dietary supplement for tilapia reared in biofloc systems. [ABSTRACT FROM AUTHOR]

Nutrient supplementations are often added to aquaponic systems to optimize plant production, and black soldier fly larvae frass is a promising organic fertilizer. However, the mineral composition of the frass is substantially influenced by the initial substrate. In an 8-week study, sweetpotato slips were cultured at commercial stocking densities in an aquaponic system which received weekly additions of either BSFL frass made from high-nitrogen expired fish diets or low-nitrogen fruits/vegetables. The sweetpotato slips (≥8 nodes) were harvested weekly. Despite differences in the mineral composition between the frass types, the water quality as well as slip production/sugar content were unaffected by frass type. The results indicate that a wide array of substrates may be suitable for producing black soldier fly larvae frass as a fertilizer in aquaponic systems. Lastly, aquaponics is a viable system to commercially produce sweetpotato slips. [ABSTRACT FROM AUTHOR]

Aquaponics is currently undergoing a transformation into an intensive food production system. The initially applied systems focused on small-scale, fish-centric coupled (CAP, the aquaculture, and the hydroponic units are arranged in a single loop, and the water flows continuously from the fish tanks to the plant unit and back) aquaponics. More recently, the primary area of research interest has shifted toward larger-scale, plant-centric decoupled (aquaculture and hydroponics units are arranged in a multi-loop setup as separate functional units that can be controlled independently) systems, aiming to achieve greater economic benefits and employ more environmentally friendly practices. The objective of this study was to address gaps in the expansion of decoupled larger-scale aquaponics and to provide a comprehensive understanding of the water and nutrient flow in the system. For this purpose, experiments were performed in a greenhouse on CAP and DCAP systems, while this study also included measurements in a pure hydroponic system (HP). This study presents an assessment of the water and nutrient flow in four different crops: basil; cucumber; parsley; and tomato, all co-cultivated with a tilapia aquaculture system. Significant nutrient deficiencies and imbalances were identified in the CAP solution, leading to pronounced impacts on nutrient assimilation, particularly for fruiting vegetables. However, the average nutrient use efficiency (NUE) for nitrogen, phosphorous, potassium, and calcium was found to be 42% higher in the CAP treatment compared to HP and DCAP treatments. The nutrient solution in the DCAP treatment did not exhibit differences in water quality parameters and nutrient efficiency when compared to HP, resulting in similar effects on nutrient assimilation. Nonetheless, it was observed that DCAP plants exhibited superior NUE compared to HP plants. [ABSTRACT FROM AUTHOR]

Aquaculture waters can be associated with the modification of the phytochemical profile in plants when they are used for irrigation; thus, Integrated Agri-Aquaculture Systems such as aquaponics represent a strategy to improve the bioactive content of medicinal plants. This study aimed to analyze the effect caused by cultivation using aquaponics on the modification of the content of bioactive compounds such as phenols, flavonoids, and apigenin in Cuphea hyssopifolia and Cuphea cyanea irrigated with Cyprinus carpio waters. The results of each culture method showed unique differences (p ≤ 0.05) in the concentrations of bioactive compounds and antioxidant activity in Cuphea spp. For C. hyssopifolia in aquaponics, 76% (61.08 ± 7.2 mg g−1 GAEq) of phenols and 50% (5.62 ± 0.5 mg g−1 CAEq) of flavonoids were maintained compared to 20% (16.99 ± 0.4 mg g−1 GAEq) of phenols and 76.5% (8.19 ± 1.6 mg g−1 CAEq) of flavonoids in conventional culture. For C. cyanea in aquaponics, 91% (15.36 ± 0.8 mg g−1 GAEq) of phenols and 47% (3.52 ± 0.6 mg g−1 CAEq) of flavonoids were maintained compared to 24% (14.11 ± 1.3 mg g−1 GAEq) of phenols and 82% (1.79 ± 0.1 mg g−1 CAEq) of flavonoids in conventional culture. An increase of more than 60% in the apigenin content of C. hyssopifolia in aquaponics confirms a eustress effect related to the use of organically enriched waters. The results indicate that aquaponics can promote the biostimulation/elicitation of medicinal plants and increase their bioactive compounds, but this effect does not occur in the same way between species. [ABSTRACT FROM AUTHOR]

In aquaponics, dissolved oxygen is essential because it feeds the aerobic bacteria that turn fish waste into plant nutrients. Sufficient quantities of dissolved oxygen guarantee the well-being of fish and plants, encouraging effective nutrient cycling and reducing the possibility of detrimental byproducts. For aquaponics systems to remain stable overall, to reduce fish stress, to improve plant development and to maintain a healthy ecosystem, ideal dissolved oxygen levels must be maintained. Monitoring and regulating oxygen levels in the pond is critical to the success of an aquaponics system. This study offers a combination approach that integrates genetic programming with long short-term memory (LSTM) models to predict short-term global solar radiation in a nonlinear manner. Time-series data can be successfully predicted using the LSTMs, which are Recurrent Neural Network (RNN) models. To employ Aquaponics data to utilize these models as core predictors of dissolved oxygen. A progressive heuristics computing method called genetic programming (GP) makes it possible to automatically find complicated solving formulas. Combining the results of LSTM models for the best overall prediction of dissolved oxygen is an attempt to use Genetic Programming (GP) at a post-processing stage. The efficiency is promoted by the suggested hybrid model. To compare the combination's performance with stacking tactics based on machine learning. The findings demonstrate that the recommended strategy significantly improves accuracy and stability. [ABSTRACT FROM AUTHOR]

In this paper, the application of the Adsorptive Stripping Voltammetry-Response Surface Methodology (AdSV-RSM) in the simultaneous determination of copper ions in an aquaponics system has been studied. The effects of several parameters studied include variations in Calcein concentration, pH, accumulation potential, and accumulation time. The study design used was Response Surface Methodology (RSM) with 4 factors/variables, 3 levels and 31 treatment combinations. The results of the study, analysis of variance was carried out, and it was decided to accept the second-order model, which means that the independent variable has a significant effect on the response variable (peak current). Based on data analysis with the RSM, the determination of Cu(II) obtained the optimum conditions including peak current 349.196 (Ip); calcein concentration 0.616339 µg/L; pH 6.06208; potential accumulation −0.721104 V and time accumulation of 69.3744 s. The response surface method has been applied successfully for Cu(II) analysis in water, fish, and hydroponic plant aquaponics system, which is an integration between fish farming and hydroponic plant cultivation, with the relative standard deviation value was 1.12%, recovery of 99.23% and the detection limit of 0.75 μg/L. [ABSTRACT FROM AUTHOR]

Introduction: Humanity is suffering from huge and severe difficulties, including changes in climate, soil degradation, scarcity of water and the security of food and medicines, among others. The aquaponics system acts as a closed loop consisting of aquaculture elements and hydroponics, which may contribute to addressing these problems. The aquaponics method is quickly expanding as the requirement to increase the production of sustainable herbal products, including medicinal compounds and foods, in freshwater systems and replenish phosphorous reserves shrinks. Methods: The current work is designed to increase the production of the antioxidants withaferin A and withanolide A in two varieties (Jawahar-20 and Poshita) of W. somnifera using the aquaponics technique. Total 100 seedlings (one month old) grown in soil initially were taken to be grown in aquaponics for a time period of 6 months. And 100 seedlings were placed in pots containing soil as control for study after six months. Results: It was observed that the higher content of withaferin A was analyzed in the root and stem samples of Jawahar-20 and Poshita from the six-month-old plant of W. somnifera. The maximum content of withanolide A was examined in the root samples of the six month-old plants of Poshita (1.879 mg/g) and Jawahar-20 (1.221 mg/g). While the 6 month old Poshita seedling grown in soil recorded less withaferin A (0.115 ± 0.009b) and withanolide A (0.138 ± 0.008d). Discussion: It is concluded that Poshita was found to be more promising for the enhanced production of withaferin A and withanolide A in the aquaponics system. Moreover, the root was observed as the best source for the production of withaferin A and withanolide A and the best age of the plant is 2 years for the production compounds in medicinal plants with futuristic perspective to hill agriculture integrated farming. compounds. Thus aquaponics can be an effective approach with enhanced yield of bioactive compounds in medicinal plants with futuristic perspective to hill agriculture and integrated farming. [ABSTRACT FROM AUTHOR]

• Nutrient dearth of K, p and fe are main hurdles for plant production in aquaponics. • Foliar application of deficient nutrients enhanced plant production in aquaponics. • Foliar spray inflates vegetative growth, yield and mineral content of okra. • Optimal fish and plant production improves the economic return of aquaponics. A 90-day study was conducted to investigate the combined effect of foliar application of macronutrients (phosphorus and potassium) and micronutrient (iron) on the performance of okra (Abelmoschus esculentus) with pangasius (Pangasianodon hypophthalmus) in an aquaponic system. A total of four treatments with variable phosphorus dosages of 2.7, 5.4, 8.1 and 10.8 g.l−1 as T1, T2, T3, and T4, respectively, in combination with 5 g.l−1 potassium and 1.0 g.l−1 iron in all treatments was compared with control. The water quality parameters were within the favourable limit for optimal aquaponic production. The foliar application of macro and micronutrients increased the vegetative growth of okra resulting in higher plant height, leaf number, length, and width in the treatments than in control, particularly in T3. A remarkable increase (p <0.05) in pod weight per plant and production of okra was observed in treatments, particularly in T3 (38.49±0.99 g per plant and 513.26±9.28 g.m−2) than the control (24.32±1.08 g.plant−1 and 324.30±18.71 g.m−2). No significant difference (p >0.05) was observed in the proximate and mineral composition of okra leaves and pods except for higher phosphorus levels in the treatment groups. The growth, haematological, biochemical and antioxidant enzyme parameters of P. hypophthalmus exhibited no significant variation (p >0.05) between the control and treatments. Thus, the study manifested that the combined foliar application of 8.1 g.l−1 of phosphorus with 5 g.l−1 of potassium and 1 g.l−1 of iron could significantly improve okra production in aquaponics. [ABSTRACT FROM AUTHOR]