During the 1950s and 1970s, with improvements in early hatchery technology and simple mechanization, aquaculture relied primarily on traditional pond and shore farming. The development of managed ponds and advances in seed production made higher stocking densities possible, while net-pen farming for yellowtail (Seriola quinqueradiata) spread rapidly throughout Japan, laying the foundation for contemporary cage-farming systems (Milne, 1972). In 1953, botanist and zoologist J.H.S. Blaxter reported the first successful attempt at cryopreservation in fish, in which he used cryopreserved sperm to fertilize herring eggs (Blaxter, 1953). The induced breeding technology for carps was developed in 1957 (Chaudhari and Alikunhi, 1957) and popularized for ensuring the quality of seed. The commercial cage farming of Atlantic salmon (Salmo salar) began in Norway in 1960, and similar system was soon adopted by other countries (Grøttum and Beveridge, 2007). At the same time, the scientific foundations of biofloc technology (BFT) were being established and practical studies on microbial flocs began in the early 1970s at Ifremer (France) and the Waddell Mariculture Center in the United States, although the idea was first proposed in the 1960s. These fundamental developments laid the foundation for more complex, technology-based systems developed in subsequent decades.

Aquaculture for shrimp and finfish expanded rapidly in this era, particularly in Asia and Latin America. Hatchery development, technological advances, and global market demand led to rapid production growth. However, this boom was also accompanied by serious environmental problems, such as eutrophication, mangrove destruction, and frequent disease outbreaks due to uncontrolled growth. To address these problems, scientists began investigating closed water circulation and recirculation systems. This led to the development of contemporary recirculating aquaculture systems (RAS), which subsequently revolutionized intensive farming methods (Ghosh, 2022; Mugwanya et al., 2022). In 1988, the first commercial application of BFT was realized in Tahiti (Emerenciano et al., 2013). Early aquaponics experiments also emerged during this period (Lennard, 2017). These programs were the first major steps toward more biosecure and sustainable aquaculture practices.

During this period, aquaculture development focused primarily on improving integrated farming methods. The development of recirculating aquaculture systems (RAS) significantly formalized the technology. RAS was made possible by advances in biofiltration, pumping efficiency, water treatment, and automation, leading to the transformation from experimental models to pilot-scale commercial operations (Ali et al., 2025; Lindholm-Lehto, 2023; Gupta et al., 2024). At the same time, studies on the integration of microalgae into RAS gained momentum, emphasizing their functions in nutrient absorption, CO₂ sequestration, and oxygen production, facilitating the development of more closed-loop and efficient production systems (Ende et al., 2024). This decade also saw the development of the concept of integrated multi-trophic aquaculture (IMTA), which encourages the ecological engineering of farms by co-culturing host species with extractive species such as seaweeds and bivalves to improve environmental performance and utilize waste nutrients (Chopin, 2011). The ecological and technological basis for the precise and sustainable production model that would be developed over the next ten years was established at this time.

This period marked a major shift, with cutting-edge sustainable technologies rapidly being adopted commercially. Established over the past decades, biofloc technology (BFT) has rapidly expanded commercially as a low-water exchange, high-efficiency production system, especially for tilapia and shrimp. BFT improves feed utilization and water quality by converting nitrogenous wastes into microbial biomass, which has attracted intensive aquaculture (Avnimelech, 2009; Yu et al., 2023). In parallel, governments and academic organizations promoted IMTA and aquaponics as sustainable nutrient recycling methods, and recent advancements have focused on incorporating innovative system designs and digital tools to enhance sustainability and efficiency. By combining multi-trophic species with hydroponic techniques (such as NFT and floating raft systems), modern IMTA-aquaponics research demonstrates improved nutrient and water use efficiency and reduced effluent discharge, enabling greater nutrient retention and total biomass production compared to monoculture (Goda et al., 2024; Ghosh et al., 2025). Furthermore, IoT sensors, artificial intelligence, and machine learning are now being integrated into smart aquaponics systems for automated control and real-time monitoring of water quality and nutrient cycling, increasing yields and resource efficiency while reducing labor input (Niranjan et al., 2020; Gayam et al., 2024; Nair et al., 2025). The development of open sea cage culture has provided a new dimension to the mariculture in India and in the year 2007, the first open sea cage was launched in Bay of Bengal off Visakhapatnam coast (Philipose et al., 2012).

Technology has been rapidly integrated into the industry, moving from traditional to data-driven smart farming. The use of automated sensors and real-time monitoring systems for variables such as pH, temperature, and dissolved oxygen has significantly improved decision-making and system management. Automation, IoT-based monitoring, artificial intelligence, and analytics have led to the development of precision aquaculture, which reduces risk and increases production (Lindholm-Lehto, 2023). Meanwhile, ecological farming methods such as aquaponics, BFT, and IMTA gained greater use and support from both research and policy frameworks. Throughout this decade, the combination of ecological sustainability and innovative technology made climate-resilient, resource-efficient aquaculture systems possible.

The aquaculture industry has recently entered a new era characterized by digital transformation, climate resilience, and circular bioeconomy models. Since 2020, AI and digitalization technologies have been widely adopted, especially in large-scale operations for high-value species such as shrimp and salmon. By combining predictive analytics, real-time control, and automated monitoring, these systems improve environmental performance and biosecurity (Gupta et al., 2024). To complement nutrient cycling and reduce energy costs, more research is being conducted on integrating microalgae-based systems into RAS (Ende et al., 2024). In addition to enhancing water quality and reducing feed inputs, BFT applications have also expanded to include shellfish production (Manan et al., 2024; Minaz et al., 2024). With the help of machine learning, precision aquaculture based on IoT and AI is improving water quality control and feeding schedules (Lindholm-Lehto, 2023). Significant progress has also been made in sustainable alternative feeds such as single-cell protein, algae oil, and insect meal, which significantly reduce dependence on fishmeal and fish oil and support circular production models (Yu et al., 2023). Taken together, these advances represent an advanced stage in aquaculture development that combines ecological sustainability and technological complexity.

Aquaculture inherently requires a lot of water, and improper water resource management can have detrimental ecological impacts. Intensive farming practices generate large amounts of nitrogen (N) and phosphorus (P)-rich metabolic waste and unused feed. These nutrients, when released into the open water bodies, can accumulate and cause eutrophication, increase algal blooms, create hypoxic condition, deteriorate water quality and cause disease (Li et al., 2025; Khalili and Moridi, 2025; Chakraborty et al., 2025). Climate change exacerbates these problems by altering water temperature, salinity, and dissolved oxygen levels, further stressing cultivated species and weakening system resilience. Furthermore, water scarcity in many regions is hampering fisheries development, highlighting the need for efficient water-use technologies. Saltwater is another problem for freshwater species, causing physiological stress that hinders growth and survival. It affects the traditional farming system, raising the expense of water management and forcing a shift towards less suited species or techniques (Alam et al., 2017).

Fishmeal and fish oil from wild fisheries have historically been the main sources of protein used in aquaculture production. Because overfishing reduces biodiversity and disrupts aquatic food webs, this dependence places significant pressure on marine ecosystems (Tacon and Metian, 2015). Since global fishmeal production is limited and confined to a few regions, its supply is vulnerable to regulatory changes, overfishing, and climate variability (Naylor et al., 2009). The economic viability of aquaculture enterprises is impacted by rising feed costs, which in turn increase production costs. Demand for protein-rich feed is increasing alongside the rapid growth of aquaculture, further intensifying competition with the livestock and poultry industries. Furthermore, conventional feed ingredients may contain anti-nutritional ingredients, pollutants, or environmental impacts that exacerbate ecological constraints (Gatlin et al., 2007). The industry must provide sufficient quantities of high-quality feed that meet the nutritional requirements for healthy growth, while avoiding over-reliance on wild fisheries and minimizing adverse environmental impacts.

One of the biggest obstacles to the viability of aquaculture is aquatic animal diseases. Cultured species are more susceptible to bacterial, viral, fungal and parasitic diseases due to high stocking densities, poor animal husbandry techniques, and environmental stresses (Bondad-Reantaso et al., 2005; Li, 2024). The high stocking densities of fish in aquaculture experience chronic physiological stress due to overcrowding and intense competition for food, oxygen, and space (North et al., 2006; Lupatsch et al., 2010). This stress activates the hypothalamic-pituitary-interrenal (HPI) axis, leading to prolonged release of cortisol (Flik et al., 2006; Mbiydzenyuy and Qulu, 2024). High cortisol level suppresses immunological activities by reducing leukocyte activity, antibody synthesis, and phagocytic function (Gonzalez Herrero and Kuehn, 2021). In addition to the effects mediated by cortisol, high stocking density also alters other stress-related physiological parameters such as high blood glucose and lactate levels, increased metabolic demand, oxidative stress, and impaired osmoregulatory balance (David, 1997; Elnady et al., 2017; Gyamfi et al., 2022; Bai et al., 2024). Frequent physical contact and aggressive interactions in crowded condition also weaken the primary defense barriers (Dash et al., 2018). All these factors collectively increase the pathogen load and accelerate the spread of infections within the culture system. Consequently, the fish become more susceptible to opportunistic infections, which can lead to disease outbreaks and increased mortality rates (Mishra et al., 2017). Disease outbreaks can have a detrimental impact on global trade, disrupting production cycles and causing significant financial losses (Kumar et al., 2022; Maezono et al., 2025). The World Organization for Animal Health (WOAH, formerly OIE) lists serious diseases of fish, crustaceans and molluscs that commonly affect trade and health. Antimicrobial resistance (AMR), a major threat to aquaculture systems and public health, also results from the excessive use of antibiotics and chemical treatments for disease control (Schmidt et al., 2000; Preena et al., 2020). Climate change, declining water quality, and the movement of living aquatic organisms all contribute to the establishment and spread of diseases.

Aquaculture, if not properly managed, it can severely harm the environment. According to Primavera (2000), coastal aquaculture development often leads to the destruction of fragile habitats essential for biodiversity and ecosystem services, such as mangroves, wetlands, and estuarine ecosystems. Ecological concerns include genetic inbreeding with wild populations, competition for resources, and disruption of local food webs when farmed animals escape into natural habitats (Atalah and Sanchez-Jerez, 2020). Furthermore, water quality, sediment chemistry, and surrounding biodiversity can all be affected by pesticides, antibiotics, and nutrient-rich wastewater from aquaculture operations (Boyd and McNevin, 2015).

Sustainability in aquaculture encompasses socio-economic and administrative aspects, in addition to environmental ones. In India, small-scale farmers often face significant barriers that prevent them from implementing cutting-edge sustainable technologies, such as limited access to markets, capital, and technology. For example, a study by Haryanto (2023) emphasizes the importance of financial support for small-scale farmers, demonstrating how access to finance from both formal and informal sources impacts food production and technical efficiency. Sustainable development is further hampered by unequal distribution of resources, weak policy frameworks, and ineffective regulation. The challenges faced by small-scale fisheries, such as poor infrastructure and limited space for investment and innovation, are recognized in the National Fisheries Policy, 2020. Concerns regarding food safety, product quality, and environmental impacts also influence societal acceptance of aquaculture operations. According to a FSN, 2025 survey, over 80% of Indians are concerned about food security, highlighting a serious public perception problem that could impact the expansion and long-term viability of the aquaculture industry.

One of the most innovative and environment friendly developments in modern aquaculture is recirculating aquaculture system (RAS). Compared to traditional techniques, these closed-loop production systems typically use 90-95% less freshwater because they reuse water (Timmons et al., 2002). RAS significantly reduces waste emissions and environmental impacts, while also providing a high level of environmental control that allows for efficient use of labor and space (Yogev et al., 2021). Mechanical filters, biological filters and UV radiation are some of the essential elements in a RAS system for water treatment and reuse (Xiao et al., 2019; Ranjan et al., 2023). While biological filtration uses nitrifying bacteria to convert toxic ammonia and nitrite into less dangerous nitrate, mechanical filtration removes suspended matter, including uneaten feed and feces (Martins et al., 2005). Additional equipment’s such as temperature regulator and oxygenation unit promise ideal for culture conditions. Due to controlled conditions and minimal water usage, these techniques are suitable for a wide variety of aquatic organisms (Table 2).

To enhance the efficiency of water reuse, modern disinfection and oxidation technologies, including ultraviolet (UV) irradiation and ozonation, are being increasingly employed in addition to conventional mechanical and biological filtration. The UV treatment in culture system efficiently inactivates pathogenic microorganisms without leaving harmful residues, while ozonation oxidizes dissolved organic matter, reduces color and odor, and improves biofilter performance by reducing the organic load before nitrification (Badiola et al., 2012; Malone and Pfeiffer, 2006). Recently discovered ammonia oxidizers, such as ammonia-oxidizing archaea (AOA) and complete ammonia oxidizers (comammox Nitrospira), which can directly oxidize ammonia to nitrate within a single organism, have also been incorporated into recent advancements in RAS biofiltration, surpassing traditional ammonia-oxidizing bacteria (Nitrosomonas and Nitrobacter). These microbial groups are now considered significant contributors to stable nitrification under low-ammonia and low-oxygen conditions, which are often present in intensive RAS operations (Daims et al., 2015; Van Kessel et al., 2015; Bartelme et al., 2017).

Biofloc technology (BFT), based on microbial activity to recycle nutrients within the culture unit, has become another innovative and environment friendly aquaculture technique. Bacteria, algae, protozoa, and organic matter are all part of the diverse microbial community generated by this system (Hargreaves, 2013; Robles-Porchas et al., 2020). BFT reduces the need for water exchange and the discharge of nutrient-rich waste into natural water bodies by encouraging water reuse over multiple cycles (Krummenauer et al., 2014). In this system, host bacteria produce microbial protein aggregates called “bioflocs” from leftover feed and excreta. Cultured species such as fish and shrimp (Table 2) can consume these flocs, increasing feed efficiency and providing an additional source of protein. Studies have shown that BFT enhances environmental control and promotes optimal yields at high stocking densities (Da Silveira et al., 2020; Schveitzer et al., 2024).

The addition of external carbon sources to control the carbon-nitrogen (C:N) ratio and promote the growth of beneficial heterotrophic microbial communities is a crucial management strategy in biofloc system. There are several carbon sources like molasses, wheat flour, rice bran, tapioca flour, cassava powder, jaggery and other agro-industrial by-products have been effectively used to maintain C:N ratio (Wei et al., 2016; Ezhilarasi et al., 2019; Rind et al., 2023). These carbon sources are considered ecological and economical options because they are often derived from locally available agricultural waste and help the system recycle nutrients by converting inorganic nitrogenous waste into microbial biomass (Avnimelech, 1999; Crab et al., 2012; Wei et al., 2016). In addition to improving water quality, the resulting microbial flocs provide an additional source of protein-rich feed for the cultured organisms, increasing feed utilization efficiency and system sustainability (Emerenciano et al., 2013; Hargreaves, 2013). However, there are serious risks associated with poor C:N ratio control in BFT systems, such as disease outbreaks and system instability. If the carbon-nitrogen (C:N) ratio is not properly maintained, the excessive growth of heterotrophic bacteria can lead to oxygen depletion, accumulation of suspended solids, and inhibition of the autotrophic nitrifying bacteria responsible for ammonia oxidation (Michaud et al., 2006). Such imbalances in the culture system can lead to increased levels of ammonia or nitrite, as well as an increased risk of opportunistic infections in the organisms (Avnimelech, 2009; Martins et al., 2010). Therefore, regular monitoring and control of carbon inputs are essential to maintain microbial balance, prevent harmful microbial communities from becoming dominant, and guarantee the health and biosecurity of BFT-based aquaculture systems (De Schryver et al., 2008; Ekasari et al., 2014).

Integrated Multi-Trophic Aquaculture (IMTA) is a sustainable farming approach that combines fed species with extractive species (Table 2) that utilize organic and inorganic wastes for growth (Barrington et al., 2009; Khanjani et al., 2022). In many traditional monoculture systems, species are cultivated independently, leading to nutrient accumulation and environmental damage. By bringing together organisms from different trophic levels, IMTA facilitates the movement of nutrients and energy through the water. By producing a variety of products and reducing production risks, this integrated system not only increases economic sustainability but also improves environmental sustainability by preventing eutrophication and recycling nutrients (biomimetics). Additionally, it improves social acceptance of aquaculture by demonstrating better farm management and ecologically conscious techniques (Sasikumar and Viji, 2016). IMTA is not the same as finfish polyculture, which can disrupt ecosystems because co-cultured species share similar biological and chemical processes. IMTA, on the other hand, deliberately mixes species with complementary ecological roles; inorganic extractive species (seaweeds) collect liquid nutrients, organic extractive species consume particulate organic compounds, and feeder species supply waste nutrients. This technique is a potential strategy for sustainable aquaculture because it allows for more intensive farming while maintaining ecological balance (Choudhary et al., 2025).

Modern IMTA systems are incorporating IoT-based real-time water quality monitoring to continuously track dissolved oxygen, nutrients, pH, and temperature to effectively manage multiple trophic levels and mitigate environmental concerns (Ruiz-Vanoye et al., 2025). In advanced IMTA setups, artificial intelligence and data-driven decision-support technologies are already being used to predict nutrient flows, optimize species combinations, and improve feeding efficiency (Peres da Silva, 2021; Ruiz-Vanoye et al., 2025). Integrating biofloc systems with soilless plant production (FLOCponics), which improves nutrient recycling through microbial biomass and simultaneously producing fish and plants, is another emerging technology (Pinho et al., 2022). The advancements in system design including modular and recirculating IMTA units further enhance resource use efficiency (Biswas et al., 2020).

Aquaponics is an integration of hydroponic and aquaculture methods in a single system that create a closed-loop structure by fertilizing plants with nutrient-rich water from fish tanks and then recirculating the treated water back into the fish tanks (Roosta and Mohsenian, 2015; Thomas et al., 2019; Baganz et al., 2022; Stoyanova et al., 2024). Aquaponics achieves water reuse rates of 95-99%, while requiring very little water exchange, effectively recycling nutrients, and significantly reducing wastewater emissions (Goddek et al., 2019; Baganz et al., 2022; Manan et al., 2025). This system has many benefits, such as reduced dependence on external fertilizers, improved water quality, elimination of the need for additional filter systems, and the ability to produce suitable fish and plants species simultaneously (Table 2), thereby increasing sustainability and profitability (Shafahi and Woolston, 2014; Eck et al., 2019). Additionally, aquaponics supports the United Nations Sustainable Development Goals, specifically Goal 2 (Zero Hunger) and Goal 14 (Life Below Water), and helps ensure food security (Goddek et al., 2019; An et al., 2021).

However, recent developments in new system designs, algal co-cultivation, micro-nanobubble technology, biofilter media, and system automation with robotics, artificial intelligence, and the Internet of Things can improve real-time control of water quality parameters, feeding efficiency, freshwater replenishment rates, and nutrient balance in aquaponics (Alselek et al., 2022; Gayam et al., 2024; Chandramenon et al., 2024). Improvements in modular, scalable, and vertical aquaponics systems have enhanced space and resource utilization efficiency, particularly in urban farming settings (Birdawade et al., 2025). These technological advancements strengthen aquaponics as an essential component of integrated multitrophic aquaculture and circular food production systems.

The approach to increasing aquaculture productivity through the focused application of technology and automation principles is known as precision aquaculture (Føre et al., 2018). The primary goal of precision aquaculture is to transform the industry from current production patterns, which are primarily manual and experience-based, to a more automated and knowledge-based one (Figure 2). As a result, farmers are able to better monitor and exercise greater control over their fish and surroundings. For aquaculture applications, more advanced and reliable sensors are available that measure water quality parameters such as temperature, oxygen, nitrogen, salinity, and turbidity. With the development of computer vision technology, studies have increased using cameras and imaging-based systems, along with algorithms to extract and analyze the data, as a non-invasive, inexpensive way to track and monitor fish in aquaculture (Zion, 2012; Qian et al., 2016; An et al., 2021; Barreto et al., 2022; Georgopoulou et al., 2021). Low-cost sensor systems and regression techniques have achieved 76-97% accuracy in measuring key water quality parameters such as temperature, dissolved oxygen, and pH in Asian seabass fisheries (Jais et al., 2024). Automated classification of shrimp health using image datasets has helped in early disease detection with deep neural networks (Islam et al., 2025; Zakaria et al., 2025). Improved feeding precision demonstrated by YOLOv8-based computer vision models in tilapia farming has enabled biomass estimation with 94% accuracy and combined with IoT sensors optimized feed use (Hossam et al., 2024). Predictive modeling integrating GIS and machine learning has further aided disease forecasting in shrimp farms, facilitating preventative management of diseases (Khiem et al., 2022). Despite challenges related to sensor reliance, investment costs, and data interoperability, evidence confirms the important role of precision aquaculture in reducing feed costs, preventing disease outbreaks, and promoting environmental sustainability (Su et al., 2020; Rastegari et al., 2023; Future Market Insights, 2025).

Biotechnology and genetic enhancement are increasingly being used to increase sustainability, resilience, and productivity in aquaculture. In species such as carp, tilapia, and salmon selective breeding techniques improving feed efficiency, growth performance and disease resistant (Gedrem and Robinson, 2014). To address production problems and accelerate genetic gain, genomic tools such as marker-assisted and genomic selection are increasingly being used (Houston et al., 2020). In addition to genetic improvement, health management techniques such as probiotics, immunostimulants, and oral vaccinations have helped reduce antibiotic dependence and mitigate the impact of bacterial infections in farmed fish (Farooqi and Qureshi, 2018). Additionally, CRISPR-Cas9 and other gene-editing technologies are becoming effective tools for targeting specific traits (Table 3). Taken together, these developments reduce disease risk, enhance production efficiency, and promote product quality.

One of the most significant developments in aquaculture is the use of alternative sustainable feeds, which address the financial and environmental problems posed by excessive reliance on fishmeal and fish oil. Aquatic feeds are being produced using sustainable feed ingredients such as single-cell proteins, microalgae, yeast, insect meal and agricultural byproducts. By reducing reliance on wild fisheries, these alternatives save marine resources and help conserve biodiversity (Turchini et al., 2019). In addition to promoting a circular bioeconomy by valuing food and agricultural waste streams, they also reduce the environmental impact of aquatic feed production by using less land and emitting fewer greenhouse gases than conventional ingredients (Henry et al., 2015). Some of these ingredients have already been incorporated into practical diets by commercial aquatic feed enterprises. For example, salmonid and shrimp aquaculture has effectively utilized black soldier fly larva meal as a protein source, demonstrating growth rates comparable to traditional fishmeal-based diets (Nogales-Merida et al., 2019). Similarly, microalgae-derived oils rich in omega-3 fatty acids have been incorporated into salmon diets, successfully replacing fish oil without compromising fillet health or quality (Zatti et al., 2023). Single-cell proteins derived from bacteria and yeast are also becoming increasingly popular as scalable solutions because they contain high protein content and useful bioactive that support immune and gut health (Koukoumaki et al., 2024). When these sustainable diet options are used together, they reduce environmental pressure, improve resource efficiency, and promote the long-term expansion of the aquaculture industry (Figure 3).

Despite the sustainability benefits of modern aquaculture technologies, they also have several drawbacks. Recirculating aquaculture systems require initial high capital investment, trained labor, and a continuous energy supply for aeration and bio-filtration to maintain stocks (Badiola et al., 2012; Malone and Pfeiffer, 2006). Biofloc technology requires continuous aeration and the adequate amount of carbon-nitrogen ratio for oxygen management and to control high levels of suspended solids and disease outbreaks (Avnimelech, 2009; Schveitzer et al., 2024). The widespread adoption of integrated multi-trophic aquaculture systems is hindered by site-specificity, species compatibility, system complexity, and regulatory issues (Barrington et al., 2009; Khanjani et al., 2022). Aquaponics systems sometimes face nutrient deficiencies, high setup costs, and limited crop options. They also require a careful balance of fish, plant, and microbial populations (Goddek et al., 2019; Baganz et al., 2022). In developing countries high sensor costs, data reliability issues, poor interoperability, and dependence on stable electricity and internet connectivity limit precision aquaculture technologies (Su et al., 2020; Flores-Iwasaki et al., 2025). Genetic improvement and gene-editing techniques also face challenges such as off-target mutations, ethical and biosecurity concerns, high costs, patent-related obstacles, low public acceptance and long-term environmental and health risks (Gutási et al., 2023). Despite the benefits of sustainability, alternative feeds present challenges such as higher costs, inconsistent nutrient composition, antinutritional factors, deficiencies in amino acids and phosphorus, low omega-3 content, palatability issues, and the potential for contaminants like mycotoxins, heavy metals, and pesticide residues (Zlaugotne et al., 2022). Insects, microalgae, and single-cell proteins face additional difficulties due to high nucleic acid concentrations, digestibility issues, sensory quality concerns, and the need for advanced processing techniques (Xu et al., 2025).