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Biofloc Technology

Biofloc Technology (BFT) is a sustainable aquaculture system that leverages microbial communities, including bacteria, algae, and organic particles, to form dense aggregates known as bioflocs, which recycle nutrients from waste, maintain water quality, and serve as a natural feed source, thereby enabling high-density production with minimal or zero water exchange.^[1] Originating in the 1970s through early experiments at the French Research Institute for Exploitation of the Sea (IFREMER) in Tahiti led by Gérard Cuzon, BFT gained prominence in the 1990s and 2000s via pioneering research by scientists such as Yoram Avnimelech in Israel and Wilson Wasielesky in Brazil, who demonstrated its efficacy in zero-water-exchange shrimp farming.^[1] The technology's core principles revolve around manipulating the carbon-to-nitrogen (C/N) ratio—typically 10:1 to 20:1—by adding carbon sources like molasses or glucose to stimulate heterotrophic bacteria, which rapidly assimilate toxic ammonia and nitrite into microbial biomass, thus preventing accumulation of harmful compounds and supporting self-purification in culture systems.^[2] This process not only stabilizes water parameters but also converts up to 30% of nitrogen waste into protein-rich bioflocs that contribute 10-30% of the nutritional needs for cultured species, reducing reliance on commercial feeds.^[1] BFT offers substantial benefits, including improved growth performance—such as 44-46% weight gain in Nile tilapia—and survival rates exceeding 96% in species like African catfish under optimized conditions, alongside enhanced immune responses and disease resistance against pathogens like Vibrio bacteria through competitive exclusion and probiotic effects.^[3] Economically, it lowers feed conversion ratios by up to 30%, cuts water usage and effluent discharge by minimizing exchanges, and decreases operational costs for aeration and waste management, promoting environmental sustainability amid rising global aquaculture demands projected to nearly double by 2050 according to assessments including the Food and Agriculture Organization (FAO).^[4] Primarily applied to marine and freshwater species such as whiteleg shrimp (Litopenaeus vannamei), Nile tilapia (Oreochromis niloticus), and common carp (Cyprinus carpio), BFT has enabled commercial yields of 11-26 metric tons per hectare per cycle in systems like those in Belize since the mid-1990s, though challenges persist in managing high aeration energy needs, floc density, and species-specific adaptations.^[3]

Fundamentals

Definition and Principles

Biofloc technology (BFT) is a zero- or low-water exchange system in aquaculture that leverages microbial communities to recycle nutrients from waste into protein-rich flocs for consumption by cultured animals. This approach enhances water quality by converting toxic nitrogenous compounds, such as ammonia, into microbial biomass while minimizing effluent discharge and promoting sustainability in intensive production.^[5] The foundational principles of BFT revolve around maintaining a carbon-nitrogen (C:N) balance, typically at a ratio of 10:1 to 20:1, to favor the proliferation of heterotrophic bacteria over nitrifying bacteria. This ratio ensures efficient nutrient uptake by stimulating bacterial growth that assimilates ammonia directly into cellular protein, thereby reducing free ammonia levels in the water column. BFT functions as a suspended-growth system, characterized by continuous aeration that keeps organic particles in suspension, leading to the formation of bioflocs—aggregates comprising bacteria, algae, protozoa, and particulate organic matter. By integrating biofiltration (nitrogen removal) and supplemental nutrition (flocs as feed) within the same culture environment, BFT optimizes resource use and reduces reliance on external inputs.^[6]^[7]^[1] In operation, carbon sources like molasses or starch are added to the system to drive the microbial process, where heterotrophic bacteria rapidly consume ammonia produced from animal waste and uneaten feed. This assimilation transforms waste nitrogen into bacterial biomass incorporated into bioflocs, which animals graze upon, providing a natural protein source that can reduce the requirement for commercial feed by 20-30%. The overall flow promotes a closed-loop nutrient cycling, maintaining stable water parameters and enhancing biosecurity by limiting pathogen introduction through water exchange.^[7] Ammonia reduction in BFT primarily occurs through heterotrophic bacterial assimilation, as simplified in the following equation:

\ce{NH4+ + organic\ C ->[heterotrophic\ bacteria] biomass + CO2 + H2O}

This process immobilizes nitrogen into microbial protein, preventing toxic accumulation and supporting floc formation.

Historical Development

Biofloc technology originated in the early 1970s at the French Research Institute for Exploitation of the Sea (IFREMER) in Tahiti, French Polynesia, where pioneering experiments focused on shrimp species under conditions of limited water availability.^[1] This initial development addressed water scarcity challenges in aquaculture, with key contributions from researcher Gérard Cuzon, who collaborated with U.S. private corporations to refine heterotrophic bacterial systems for nutrient recycling.^[1] By the 1980s, parallel advancements occurred in Israel, where Yoram Avnimelech at the Technion-Israel Institute of Technology explored heterotrophic systems in tilapia ponds, emphasizing microbial conversion of waste into protein sources to minimize water exchange.^[1] In the 1990s, research intensified in the United States at the Waddell Mariculture Center under J. Stephen Hopkins, leading to the first commercial applications in shrimp farming in Belize by the mid-decade.^[1] This period marked broader adoption in Latin America, including Ecuador, and Asia, driven by viral disease epidemics in traditional shrimp ponds that necessitated biosecure, low-water systems.^[8] A seminal advancement came with publications on zero-water exchange systems, such as those building on Avnimelech's work, which demonstrated scalable heterotrophic biofloc for intensive production without effluent discharge.^[9] The 2000s saw expanded studies in the Americas, with Wilson Wasielesky at the Federal University of Rio Grande in Brazil and Tzachi Samocha at Texas A&M University standardizing protocols for diverse species like shrimp and tilapia.^[1] International bodies, including the Food and Agriculture Organization (FAO), promoted sustainable intensification in aquaculture through guidelines, aligning it with global efforts to reduce aquaculture's environmental footprint.^[10] Post-2010, commercial systems proliferated in India and Brazil, transitioning from experimental setups to industrial-scale operations amid rising demand for water-efficient methods.^[11] Global adoption accelerated from niche research to widespread industrial use, particularly in Asia and Latin America, supported by sustainability objectives like the United Nations Sustainable Development Goals (SDGs), especially SDG 14 on life below water.^[12] Between 2015 and 2025, adoption surged due to climate-driven water conservation needs, positioning biofloc as a resilient adaptation strategy in regions facing scarcity and environmental pressures.^[13] By the early 2020s, biofloc enabled higher yields with minimal resource use.^[14]

Biological Components

Role of Microorganisms

Microorganisms form the cornerstone of biofloc technology, driving nutrient cycling and water quality maintenance through diverse bacterial, protozoan, and algal communities. Heterotrophic bacteria, such as Bacillus and Pseudomonas species, serve as primary floc builders by rapidly proliferating in response to organic carbon inputs, forming the bulk of biofloc aggregates. Autotrophic nitrifying bacteria, including Nitrosomonas and Nitrobacter, facilitate ammonia oxidation, while protozoa and algae contribute to floc stabilization by grazing on excess bacteria and providing structural integrity, respectively.^[1]^[7]^[15] The primary functions of these microorganisms revolve around nitrogen management and bioremediation. Heterotrophic bacteria assimilate dissolved ammonia nitrogen (NH₃ or NH₄⁺) into microbial biomass, which can contain up to 50% protein on a dry weight basis, thereby converting potentially toxic waste into a nutritious supplement for cultured organisms. Autotrophic nitrifiers perform sequential oxidation: Nitrosomonas converts ammonia to nitrite via the reaction

\text{NH}_4^+ + 1.5\text{O}_2 \rightarrow \text{NO}_2^- + \text{H}_2\text{O} + 2\text{H}^+

followed by Nitrobacter transforming nitrite to nitrate through

\text{NO}_2^- + 0.5\text{O}_2 \rightarrow \text{NO}_3^-.

Collectively, these processes enable bioremediation by decomposing organic matter and effectively reducing total ammonia nitrogen (TAN) levels in optimized systems, preventing accumulation of harmful compounds.^[1]^[7]^[16] Microbial interactions in biofloc systems are predominantly symbiotic, enhancing overall efficiency. Heterotrophic bacteria provide organic substrates that support protozoan and algal growth, while protozoa regulate bacterial populations through predation, maintaining floc balance and preventing dominance by any single group. Algae, in turn, release oxygen and fixed carbon that benefit bacterial metabolism. These dynamics are highly sensitive to environmental conditions: optimal pH ranges of 7-8 promote nitrifier activity and heterotrophic growth, whereas dissolved oxygen levels above 4 mg/L are essential to sustain aerobic processes and avoid anaerobic shifts that could produce toxic byproducts.^[1]^[7]^[15]

Biofloc Formation and Dynamics

Biofloc formation in aquaculture systems is initiated by introducing organic carbon sources, such as molasses or wheat bran, to establish a carbon gradient that promotes heterotrophic bacterial growth and nitrogen assimilation. These carbon inputs, typically added at rates equivalent to 10-20 times the total ammonia nitrogen (TAN) concentration, stimulate the aggregation of microorganisms into flocs within 24-48 hours under continuous aeration. The resulting microbial aggregates, known as bioflocs, range in size from 50 to 200 μm, forming dense clusters that enhance water quality by immobilizing dissolved nutrients.^[9] The composition of bioflocs primarily consists of microbial biomass bound together by extracellular polymeric substances (EPS), which comprise 80-95% of the organic matter and facilitate floc stability through their gel-like matrix of polysaccharides and proteins. On a dry weight basis, bioflocs typically contain 12-50% protein and 0.5-41% lipids, varying with carbon source and environmental conditions, while the remaining fractions include carbohydrates (14-59%) and ash (3-61%). Density and settleability are key properties, often quantified by floc volume, with an optimal range of 10-20 mL/L indicating balanced aggregation without excessive solids accumulation.^[17]^[18]^[19] Biofloc dynamics are governed by environmental factors that influence maturation and stability, including aeration rates of 0.1-10 W/m³ to maintain suspension and prevent settling at rates of 1-3 m/h. Salinity levels between 5 and 35 ppt support diverse microbial communities, while temperatures of 25-32°C optimize floc development; deviations, such as exceeding 32°C, can lead to excessive EPS production and floc bulking. Imbalances in the C:N ratio, particularly below 10:1, cause floc degradation through ammonia accumulation and reduced bacterial efficiency, disrupting overall system homeostasis.^[20] Monitoring biofloc concentration relies on the Imhoff cone method, where a 1 L water sample is allowed to settle for 10-20 minutes to measure settled floc volume, ensuring it remains within the optimal 10-20 mL/L to avoid oxygen depletion or poor water clarity. Floc loading rates can be estimated using the equation for biomass production:

\text{Biomass production} = \frac{\text{C input} \times \text{efficiency}}{\text{N demand}}

where efficiency reflects carbon conversion to microbial biomass (approximately 0.4 g biomass per g C input), and N demand is based on TAN levels, guiding carbon additions to sustain floc quality.^[9]^[21]

System Design and Operation

Key Components and Setup

Biofloc systems rely on specialized infrastructure to support microbial activity and maintain water quality in a controlled environment. Core components include lined ponds or tanks, which are typically round to promote efficient mixing and prevent dead zones, with depths of 1 to 2 meters to optimize oxygen distribution and floc suspension. These are constructed using high-density polyethylene (HDPE) liners, 30-40 mil thick, to ensure impermeability and durability against erosion. For smaller installations, tanks made from tarpaulin, fiberglass, or HDPE are common, often with capacities of 15,000 liters or more per unit. Aeration systems form another essential element, utilizing paddlewheel aerators or fine-bubble diffusers to deliver 25-35 horsepower per hectare, maintaining dissolved oxygen levels above 5 mg/L while constantly agitating the water to keep bioflocs in suspension. Carbon source dosing equipment, such as manual or automated pumps, is integrated to precisely add carbohydrates like molasses, wheat flour, or tapioca, targeting a carbon-to-nitrogen (C:N) ratio of 10-20:1 for heterotrophic bacterial growth. Setting up a biofloc system begins with site selection in shaded, low-evaporation locations to reduce water loss and temperature fluctuations, ideally in areas with access to reliable power for aeration and minimal contamination risks. Following construction, the system is filled with water and inoculated with mature biofloc from an established source, typically comprising 10-20% of the total volume, to jumpstart the microbial community; alternatively, initial bacterial seeding can use pond soil, ammonium sulfate, and carbon sources in a separate maturation phase lasting several days. Initial stocking occurs once floc density reaches 10-50 mL/L, with densities such as 300-500 post-larvae per square meter for shrimp or 150-300 juveniles per cubic meter for tilapia, depending on species tolerance to high solids.^[22]^[23] Systems vary in scale from small backyard setups with tanks under 100 m³, suitable for experimental or hobbyist use, to commercial operations covering 0.1-2 hectares in lined ponds for higher yields of 20-25 tons per hectare. Initial setup costs for a 0.1-hectare pond range from approximately $12,000 to $18,000 USD (as of 2024 estimates), encompassing liners, aeration, and basic infrastructure, while larger scales increase proportionally due to expanded equipment needs. Water management emphasizes zero or minimal exchange, with excess solids and sludge removed every 2-4 weeks via settling basins or clarifiers to prevent accumulation beyond 500 mg/L total suspended solids, thereby sustaining system stability.

Management Practices

Effective management of biofloc systems requires consistent daily interventions to sustain water quality and microbial activity. Aeration must be regulated to ensure dissolved oxygen (DO) levels remain above 5 mg/L, preventing hypoxic conditions that could harm cultured species and floc-forming bacteria.^[24] Carbon dosing, typically using sources like molasses or glucose, is adjusted based on total ammonia nitrogen (TAN) measurements to promote heterotrophic bacterial growth and nitrogen assimilation, often targeting a carbon-to-nitrogen (C/N) ratio of 15:1.^[25] Feed management involves reducing conventional inputs by 20-30% compared to clear-water systems, as bioflocs serve as a supplemental protein source, improving feed conversion ratios to around 1.2-1.3.^[26] These practices leverage the microbial communities' role in nutrient recycling to minimize waste accumulation.^[3] Routine monitoring is essential for system stability, with weekly assessments of key parameters using test kits or probes. pH should be maintained between 7 and 8.5, often through additions of sodium bicarbonate if fluctuations occur, while total alkalinity is kept above 100 mg/L as CaCO₃ to buffer against acidification from nitrification.^[25] Floc quality is evaluated visually and via settleability tests to ensure dense, protein-rich aggregates, and probiotics such as Bacillus species are periodically introduced to bolster beneficial microbial populations and suppress pathogens.^[26] Daily TAN and DO checks guide immediate adjustments, preventing imbalances that could disrupt floc formation.^[7] Harvesting and maintenance procedures help control biomass density and solids buildup. Partial harvests of cultured organisms are conducted to keep stocking densities optimal, typically every few weeks depending on growth rates, allowing for sustained production without overcrowding.^[25] Sludge management involves weekly removal of 10-20% of settled solids from the system bottom via siphoning or settling chambers to avoid excessive total suspended solids (TSS) that could reduce DO and promote anaerobic zones.^[25] Troubleshooting common issues promptly is critical to avoid system failure. In cases of floc crash—often triggered by insufficient carbon or over-aeration—operators increase carbon dosing to restore the C/N balance and enhance bacterial proliferation.^[25] For disease outbreaks, affected sections are quarantined, and ultraviolet (UV) disinfection is applied to water inflows to eliminate pathogens while preserving beneficial microbes.^[26] These responses, combined with vigilant monitoring, ensure resilience in biofloc operations.

Species Compatibility

Suitable Species

Biofloc technology is particularly effective for species that can utilize microbial flocs as a supplementary feed source, with Pacific white shrimp (Litopenaeus vannamei) serving as a primary candidate due to its rapid growth and high survival rates in floc-rich environments. In biofloc systems, L. vannamei typically achieves growth rates of 1-2 g per week under optimal conditions, supported by the nutritional contribution of bioflocs that enhance feed efficiency. Survival rates for this species often exceed 80%, reflecting its resilience to the high-density, low-water-exchange conditions inherent to biofloc setups.^[27]^[28] Nile tilapia (Oreochromis niloticus) is another primary species well-suited to biofloc systems, owing to its physiological tolerance to elevated levels of suspended solids, which are prevalent in floc-dominated water columns. This omnivorous fish can ingest and digest bioflocs, allowing it to thrive at stocking densities that would stress other species in conventional aquaculture.^[29] Secondary species such as African catfish (Clarias spp.) and common carp (Cyprinus carpio) also demonstrate compatibility with biofloc technology, exhibiting robust performance in floc-based cultures. These species benefit from the protein-rich bioflocs, which support their growth in intensive systems. Polyculture integrations, such as combining L. vannamei with O. niloticus, further optimize resource use by leveraging complementary feeding habits, where tilapia consumes excess flocs generated by shrimp activity.^[1]^[30]^[31]^[32] Key adaptations enabling success in biofloc systems include the filter-feeding capabilities of species like L. vannamei, which can derive 20-30% of their nutritional requirements directly from biofloc consumption, reducing reliance on formulated feeds. Optimal stocking densities for shrimp post-larvae (PL) in biofloc tanks range from 250-500 PL/m³, balancing growth and water quality management.^[8]^[27]^[33] Performance in biofloc systems often yields 20-40% higher production compared to traditional pond methods, attributed to improved feed conversion and reduced mortality. A standard metric for assessing growth is the specific growth rate (SGR), calculated as:

\text{SGR} = 100 \times \frac{\ln(\text{final weight}) - \ln(\text{initial weight})}{\text{days}}

This formula quantifies daily percentage weight gain, with biofloc-reared L. vannamei and O. niloticus frequently showing SGR values exceeding 2-3% per day under favorable conditions.^[34]^[35]

Limitations and Incompatibilities

Biofloc technology is incompatible with certain fish species that cannot tolerate elevated levels of total suspended solids (TSS), typically exceeding 200-500 mg/L in mature systems. Salmonids, such as those in the genus Oncorhynchus (e.g., rainbow trout Oncorhynchus mykiss and Atlantic salmon Salmo salar), are particularly unsuitable due to their preference for oligotrophic, clear-water environments and sensitivity to high TSS concentrations, which can impair gill function and reduce growth performance.^[36] Similarly, other finfish like trout require pristine water conditions and exhibit stress or mortality in biofloc setups where suspended particulates obscure visibility and alter water clarity, leading to behavioral disruptions and reduced feed intake.^[37] A primary limitation of biofloc systems is the high energy demand for continuous aeration, which maintains dissolved oxygen levels and suspends flocs but can constitute 10-25% of total operating expenses in electricity-intensive operations. In dense cultures with high stocking densities, oxygen depletion poses a significant risk, as microbial respiration and organic matter decomposition rapidly consume available oxygen, potentially dropping levels below 3 mg/L and causing mass mortality if aeration fails. Closed-system designs, while minimizing water exchange, can amplify disease risks under suboptimal management, allowing pathogens like Vibrio spp. to proliferate and trigger outbreaks, such as vibriosis, due to concentrated waste products and limited dilution.^[38]^[39]^[40] Biofloc performance is constrained in cold-water environments, where temperatures below 20°C lead to floc instability and deflocculation, as microbial activity slows and heterotrophic bacteria fail to maintain aggregate formation, resulting in poor nitrogen assimilation and system collapse. This makes the technology less viable for cold-water species and introduces scale-up challenges in temperate climates, where seasonal cooling necessitates costly infrastructure like greenhouses to sustain optimal temperatures of 28-30°C for floc dynamics. Brief microbial imbalances, such as shifts toward filamentous bacteria, can exacerbate these issues by promoting floc bulking and reduced settling. Preliminary approaches like hybrid biofloc-clear water systems or selection of cold-tolerant microbial strains offer potential adaptations, though they require further validation.^[14]^[34]^[34]

Benefits and Challenges

Advantages

Biofloc technology offers substantial environmental benefits by minimizing water usage and effluent discharge in aquaculture systems. Compared to traditional pond culture, which often requires daily water exchanges of 10-30%, biofloc systems achieve up to 90% reduction in water consumption through zero or minimal exchange practices, promoting sustainability in water-scarce regions.^[41] Additionally, the technology facilitates high removal efficiencies of nitrogen and phosphorus from effluents, exceeding 90% in optimized setups, by converting waste into microbial biomass that recycles nutrients within the system, thereby lowering the carbon footprint associated with waste treatment and discharge.^[42] Economically, biofloc technology reduces operational costs, particularly feed expenses, which constitute 50-70% of production budgets in conventional aquaculture. By leveraging bioflocs as a natural protein source—derived from microbial aggregation and dynamics—the system cuts feed costs by 20-30%, as cultured organisms consume floc particles alongside formulated feeds, enhancing overall resource efficiency.^[34] It also supports higher stocking densities, yielding 2-3 times more biomass per unit area than traditional methods, which accelerates production cycles and improves profitability for commercial farms.^[43] The global biofloc market was valued at USD 1.42 billion in 2024, with significant growth in Asia holding about 48% share and a projected compound annual growth rate (CAGR) of approximately 10% as of 2025.^[44] From a health perspective, biofloc systems bolster animal welfare by providing microbial probiotics within the flocs, which enhance innate immunity and reduce reliance on antibiotics. Studies indicate improved disease resistance in species like shrimp and tilapia, with improved survival rates against pathogens such as Vibrio spp., due to the immunostimulatory effects of biofloc components.^[45] Key performance metrics underscore these advantages, including a feed conversion ratio (FCR) of 1.0-1.2 in biofloc setups, compared to 1.5-2.0 in clear-water systems, reflecting superior nutrient utilization.^[26]

Drawbacks and Mitigation

Biofloc technology requires intensive aeration to maintain dissolved oxygen levels above 5 mg/L and suspend flocs, leading to high energy consumption that can reach 15–30 kWh per kg of biomass produced, depending on system intensity and species cultured. This energy demand stems from the elevated oxygen needs of heterotrophic bacteria and high stocking densities, often accounting for over 50% of operational costs in intensive setups.^[46]^[47] Effective implementation demands significant technical expertise for ongoing monitoring of parameters like total ammonia nitrogen (TAN) and pH, as improper management can destabilize the microbial community and compromise system performance. Biofloc overgrowth, resulting in total suspended solids (TSS) exceeding 500 mg/L, poses risks of anaerobic zones forming within aggregates, which release toxic compounds such as hydrogen sulfide and lead to sudden oxygen crashes, potentially causing mass mortality events.^[26]^[2] Scalability challenges are pronounced in developing regions, where high startup costs for infrastructure like aerators and liners—often exceeding those of traditional pond systems—limit adoption among smallholder farmers, compounded by variability in floc quality due to inconsistent carbon sources or environmental fluctuations. Certain species, such as filter-feeding bivalves, exhibit incompatibilities with dense floc environments, further restricting broad application.^[48]^[32] To address energy intensity, adoption of energy-efficient aerators, including low-speed paddlewheels or solar-powered variants, can reduce consumption by up to 60% through optimized oxygen transfer efficiency (1.1–3.3 kg O₂/kWh) and renewable integration, making systems more viable in electricity-scarce areas. Training programs for farmers, coupled with automation via IoT sensors for real-time TAN (target <0.5 mg/L) and DO tracking, minimize expertise gaps by enabling predictive adjustments and reducing response times to imbalances. Hybrid clear-water biofloc systems, which incorporate filtration to maintain lower TSS while retaining floc benefits, enhance nursery performance and consistency, particularly for species like shrimp and tilapia.^[49]^[50]^[51] Disease risks in biofloc systems arise from potential pathogen proliferation within flocs, but biosecurity measures such as UV sterilization mitigate this by inactivating bacteria like Vibrio, achieving up to 99.5% suppression and thereby reducing outbreak incidence through enhanced water disinfection without chemical residues.^[52]

Applications and Future Directions

Current Applications

Biofloc technology (BFT) has become a cornerstone of intensive aquaculture in Asia, where it dominates the global market with approximately 48% share, valued at USD 681 million in 2024. In India and Vietnam, BFT is extensively applied in shrimp farming, enabling high-density production of species like Pacific white shrimp (Litopenaeus vannamei) and black tiger shrimp (Penaeus monodon), contributing to regional seafood exports exceeding USD 5 billion annually for shrimp alone. For instance, Vietnamese farms using semi-BFT models have achieved yields of up to 24.8 tons per hectare with survival rates around 87%, while Indian operations post-2020 have scaled super-intensive systems stocking over 150 shrimp per square meter to boost output and biosecurity.^[44]^[53]^[54] In Latin America, BFT adoption focuses on both shrimp and finfish, particularly in Brazil, which has emerged as a key player in tilapia farming, where BFT enables sustainable high-density culture (up to 400 individuals per m³) with lower environmental footprints, as demonstrated in recent studies showing improved feed efficiency and waste recycling.^[55] Africa represents an emerging frontier for BFT, particularly among smallholder farmers in Nigeria, where it is applied to African catfish (Clarias gariepinus) fingerling production to enhance reproductive performance and larval quality amid limited water resources. The continent's biofloc market reached USD 85 million in 2024, driven by government initiatives for sustainable aquaculture in regions like West Africa. Beyond single-species systems, BFT is integrated into multi-trophic aquaculture (IMTA) setups worldwide, combining shrimp or tilapia with algae and detritivores to recycle nutrients and maintain water quality, as seen in combined shrimp-tilapia-algae models that improve overall productivity by 20-30%.^[56]^[44]^[57] Globally, BFT's market was valued at USD 1.42 billion in 2024, with projections for a 9.1% CAGR through 2033, fueled by its role in zero- or low-discharge facilities that now comprise a majority of intensive operations in adopting regions. In India, recent analyses of 37 shrimp farms highlight BFT's edge in sustainability, with higher profitability compared to conventional systems. These applications underscore BFT's scalability, from smallholder setups to commercial scales yielding 20-40 tons per hectare in optimized shrimp systems.^[44]^[58]^[59]

Emerging Developments

Recent innovations in biofloc technology include the development of AI-driven monitoring systems that enable predictive management of water quality parameters such as dissolved oxygen, pH, and ammonia levels. These systems integrate Internet of Things (IoT) sensors with machine learning algorithms to provide real-time data analysis and automated adjustments, reducing operational risks and improving efficiency in commercial setups. Pilots implemented post-2020 have demonstrated up to 30% improvements in fish growth rates through proactive interventions, as seen in smart biofloc applications for shrimp and tilapia farming.^[60]^[61] Genetic selection efforts focus on breeding strains of aquatic species that better utilize bioflocs as a feed source, enhancing nutrient assimilation and growth performance. While CRISPR-based editing in shrimp has advanced disease-resistant varieties, its specific application to floc-consuming traits remains in early research stages, primarily through conventional selection in integrated systems.^[62]^[63] Research frontiers emphasize the integration of biofloc technology with recirculating aquaculture systems (RAS) to support urban farming initiatives, where space and water resources are limited. Hybrid RAS-biofloc models achieve over 90% water recycling while maintaining floc-based nutrient management, enabling year-round production in controlled environments. Nanotechnology is emerging to enhance floc stability, with nano-oxygen bubbles improving nitrogen cycling and microbial activity, thus optimizing oxygen transfer and reducing energy demands in dense cultures. Additionally, efforts to develop climate-resilient variants address saline variability, as biofloc systems at varying salinities (e.g., 5-35 ppt) have shown enhanced immune responses and reproductive performance in species like Florida red tilapia.^[64]^[65]^[66] Future impacts include the expansion of biofloc applications to new species such as Asian seabass (Lates calcarifer) and marbled crayfish, where recent trials have established viable culture protocols with improved water quality and reduced feed costs. Policy frameworks promoting sustainable aquaculture are encouraging biofloc adoption through incentives for low-emission systems, potentially scaling production in regions facing water scarcity. These advancements are projected to contribute to broader sustainability goals by minimizing nutrient effluents and supporting circular economies in aquaculture.^[67]^[68] Challenges ahead involve the standardization of biofloc protocols to ensure consistent performance across diverse setups, as current variations in carbon sources and aeration methods hinder scalability. Ongoing 2025 studies highlight the need for frequent sludge management to mitigate heavy metal accumulation in effluents, with weekly removals showing lower bioaccumulation in cultured species and better overall system health. Assessments of biofloc-derived sludge indicate potential benefits for organic matter enrichment when used as fertilizer but underscore risks of contaminants if not properly treated.^[21]^[69]

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[PDF] Marine Shrimp Biofloc Systems: Basic Management Practices
Using values from Table 2, the theoretical biomass of shrimp is found. Starting size of shrimp (1.0 g) x 4 weeks' growth. (1.5 g/week) = 7 g individual shrimp.<|separator|>
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[PDF] Comparison between biofloc technology system and aquamimicry in ...
Contrarily, average survival rate > 80% in nursery with BFT treatment had been considered as a good goal in intensive shrimp farming systems (Martinez-Porchas ...
[26]
[PDF] Growth and Feed Performances of the Nile Tilapia During the ...
Apr 30, 2023 · biofloc culture should tolerate high levels of suspended solids ... (Oreochromis niloticus) reared in biofloc system on graded feeding rates.
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Biofloc: A sustainable alternative for improving the production of ...
This review aims to investigate the significance of the biofloc system in carp aquaculture with emphasis on various parameters such as water quality, growth ...Missing: guidelines | Show results with:guidelines
[28]
Integrated multitrophic culture of shrimp Litopenaeus vannamei and ...
Mar 21, 2023 · The present study aimed to evaluate two stocking densities of tilapia in an integrated culture with shrimp Litopenaeus vannamei reared in a pilot-scale biofloc ...
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Biofloc Technology (BFT) in Aquaculture: What Goes Right, What ...
Jan 11, 2024 · BFT offers a cleaner production option that promotes circularity practices while enhancing performance and economic benefits.Missing: definition | Show results with:definition
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Study backs biofloc benefits in shrimp production
Feb 19, 2019 · The use of biofloc and artificial substrates permitted doubling density from 300 to 600 PL/m3 without affecting growth, survival, feed ...Missing: 150-300 | Show results with:150-300<|separator|>
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The prospects of biofloc technology (BFT) for sustainable ...
The carbon enables heterotrophic bacteria to multiply and consume ammonia present in the water, thus maintaining low ammonia concentration. It is advisable to ...
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Specific Growth Rate - an overview | ScienceDirect Topics
SGR: (% day − 1) = 100 × [(ln final fish weight) − (ln initial fish weight)]/days fed.
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Using BioFloc Technology to Improve Aquaculture Efficiency - MDPI
The BFT contains a large number of microorganisms, including photoautotrophic microorganisms (algae), chemoautotrophic microorganisms (nitrifying bacteria), and ...
[34]
Biofloc Technology: Emerging Microbial Biotechnology for the ...
Optimum range relied on the cultured fish/shrimp species. 5–20 ml/l for tilapia fingerlings, 5–15 ml/l for shrimp, and 20–50 ml/l for adult and juveniles ...
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Economic aspects of red tilapia production using biofloc technology ...
Jan 6, 2025 · Electricity costs can account for 10–25 percent production costs in systems with electricity-intensive load, especially in recirculating ...
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Microbial Interactions, Growth, and Health of Aquatic Species ... - MDPI
Dec 9, 2022 · Many studies have demonstrated that biofloc increases the growth of aquatic species by acting as a food source or providing bioactive compounds.
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Emergence of human associated bacterial pathogens in Anabas ...
Oct 21, 2025 · In biofloc systems, pathogenic bacteria can thrive under suboptimal environmental conditions, leading to disease outbreaks. Poor water quality, ...
[38]
Biofloc Technology (BFT) in Aquaculture: What Goes Right, What ...
BFT offers a cleaner production option that promotes circularity practices while enhancing performance and economic benefits.
[39]
Optimizing carbon sources on performance for enhanced efficacy in ...
Bioflocs can efficiently achieve simultaneous nitrate and phosphate removal through a single-stage aerobic process, provided they are continuously supplemented ...Missing: efficiency | Show results with:efficiency
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Tilapia production using biofloc technology - Global Seafood Alliance
May 1, 2011 · In the author's experience, tilapia biomass can reach 200-300 mt/ha, as compared to shrimp biomass of about 20 mt/ha in well-managed ponds. This ...Saving Water, Waste... · Tan Control · Oxygen ManagementMissing: yield | Show results with:yield<|separator|>
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Biofloc Microbiome With Bioremediation and Health Benefits - PMC
The biofloc system's basic principle is to recycle and transform waste and excessive nutrients, in particular inorganic nitrogen (NH3-N and NO2-N), generated ...
[42]
Biofloc Technology Market Research Report 2033 - Dataintelo
By the end of 2033, the market is forecasted to reach USD 3.11 billion, propelled by the rising demand for high-yield, eco-friendly aquaculture systems and the ...
[43]
[PDF] resource utilization in heterotrophic - MU Extension
Production energy requirements (per lb live wt) range from 5.0 kwh/lb (fish) to 15 kwh/lb (shrimp) as opposed to 8 kwh/lb (chicken), 24 kwh (pork) and 35 kwh/lb ...Missing: consumption | Show results with:consumption
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Assessing the sustainability of tilapia farming in biofloc-based ...
According to Walker et al. (2020), the high electricity demand for aeration, water movement (to keep the bioflocs in suspension), and water pumping certainly ...
[45]
(PDF) The Future of Biofloc Development Techniques for Aquaculture
Oct 2, 2024 · One of the main problems is high initial costs due to expensive high-capacity aerators, especially when using the technology on a large scale ...
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Assessment of standard aeration efficiency of different aerators and ...
The studies showed that the aeration efficiency ranges from 1.1 kg O2/kWh to 3.3 kg O2/kWh. Show abstract.
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[PDF] Analysis of energy efficiency and financial feasibility of using solar ...
Apr 28, 2025 · The application of solar panel technology in paddle aerators can also mitigate potential energy loss, which impacts the efficiency and technical ...
[48]
IoT-based real-time biofloc monitoring and controlling system
In this study, a system was proposed that continuously analyzes biofloc regulating parameters, such as temperature, total dissolved solids (TDS), potential of ...
[49]
Integration of Biofloc and Ozone Nanobubbles for Enhanced ... - MDPI
This study pioneers the integration of ozone with biofloc technology (BFT), achieving 99.5% Vibrio suppression, 82% shrimp survival, and 61% ammonia reduction.
[50]
Expanding Semi-Biofloc technology in whiteleg shrimp farming
Shrimp grew well, with no disease, a survival rate of 87%, an average harvest size of 70 shrimp/kg, a yield of 24.8 tons/ha, and an average profit of 171 ...
[51]
(PDF) Super‐intensive shrimp culture: Analysis and future challenges
We define the super-intensive system for white shrimp, L. vannamei, as one that uses lined ponds, raceways, or tanks for stocking densities of over 150 shrimp ...<|separator|>
[52]
Comparison of resource use for farmed shrimp in Ecuador, India ...
Nov 16, 2021 · The purpose of this study was to assess the amounts of land, water, energy in fuels, and wild fish for fishmeal and fish oil in feeds required per tonne of ...
[53]
Brazilian researchers prove biofloc as sustainable solution for ...
Oct 15, 2025 · Researchers found biofloc enables efficient, high-density tilapia farming with lower environmental impact, offering a sustainable aquaculture ...Missing: applications | Show results with:applications
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Biofloc technology application in African catfish fingerling production
Aug 6, 2025 · This study demonstrates a novel research on the application of biofloc technology in broodstock and larval rearing of African catfish.
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Integrated multitrophic aquaculture system applied to shrimp, tilapia ...
Jul 15, 2023 · The biofloc technology system (BFT) can increase productivity in shrimp farming systems and other aquatic organisms, while reducing ...
[56]
New Study on Sustainable Shrimp Farming in India Reveals Key ...
Aug 4, 2025 · The research, which analyzed 37 shrimp farms, provides crucial insights into the sustainability and profitability of conventional, biofloc, and ...Missing: percentage | Show results with:percentage
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Biofloc Technology: A Simple, Green Way to Farm Fish and Shrimp
Mar 20, 2025 · ... L in an Imhoff cone for a TSS of 200-500 mg/L in Biofloc systems, averaging around 10 mL/L, depending on floc type, settling time, and ...Missing: optimal | Show results with:optimal
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Smart Biofloc Systems: Leveraging Artificial Intelligence (AI) and ...
Biofloc technology (BFT) has emerged as an effective method, leveraging microbial communities to enhance water quality, reduce feed costs, and improve fish ...Missing: surge | Show results with:surge
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Biofloc Fish Farming: AI Use in Agri & Biofloc Farms - Farmonaut
Advantages of Biofloc Fish Farming in 2025. “Biofloc technology reduces water usage in fish farming by nearly 90%, making aquaculture more sustainable and ...
[60]
Effects of biofloc on growth performance and survival of Pacific white ...
When cultivated in L. vannamei rearing systems, bioflocs assist in the recycling of nutrients, improve water quality, and inhibit the proliferation of pathogens ...
[61]
Study on floc characteristics and bacterial count from biofloc‐based ...
Dec 1, 2020 · The present study endeavoured to investigate the efficacy of biofloc technology (BFT) and clear water system (CWS) on nursery rearing of genetically improved ...
[62]
A systematic analysis of recirculating aquaculture systems (RAS ...
Aug 15, 2025 · This study analyzes recirculating aquaculture systems (RAS) and biofloc technology (BFT) for indoor white leg shrimp (Litopenaeus vannamei) farming
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The role of Pure Nano Oxygen Bubbles in the nitrogen cycle of ...
Nevertheless, biofloc accumulation can also lead to increased suspended solids, oxygen depletion, and fluctuations in microbial community dynamics (Soaudy et al ...
[64]
Salinity-dependent effects of integrated biofloc technology on ...
Jan 10, 2025 · High salinity environments led to increased dissolved oxygen but reduced pH, especially in BFT ponds. BFT improved reproductive performance, ...
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Development of aeration devices and feeding frequencies for ...
The use of biofloc technology is suitable for aquaculture under low water change conditions. It is a system that takes advantage of the flocs formed to treat ...
[66]
Establishment and characterization of biofloc culture for marbled ...
May 7, 2025 · Our study is the first to establish marbled crayfish biofloc culture and to characterize the interaction between the animals and the production system.<|control11|><|separator|>
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Integrated Application of Biofloc Technology in Aquaculture: A Review
This paper systematically reviews the action mechanisms, synergistic effects, and challenges of the four mainstream integration models incorporating BFT.Missing: unsuitable | Show results with:unsuitable
[68]
Sludge removal frequency influences heavy metal accumulation ...
May 30, 2025 · Weekly removal yielded better water quality, lower metal bioaccumulation, and enhanced growth. Findings emphasize frequent sludge management for optimal BFT ...
[69]
Impact of treated wastewater sludge on soil and wheat growth ...
Apr 25, 2025 · This research provides valuable insights into the positive effects of treated sewage sludge application on soil fertility and wheat grain quality