What is Biofloc Technology and How Can It Benefit Aquaculture?
What is Biofloc Technology and How Can It Benefit Aquaculture?
Biofloc technology (BFT) is a sustainable and environmentally friendly aquaculture system that recycles waste nutrients into microbial biomass, which can be used as a protein-rich feed source for fish and shrimp. BFT also improves water quality, reduces disease outbreaks, and lowers water consumption. BFT was developed by Dr. Yoram Avnimelech, a professor at the Technion - Israel Institute of Technology, who wrote a practical guide book on the topic.
How Does Biofloc Technology Work?
Biofloc technology works by maintaining a high carbon to nitrogen ratio (C:N) in the water, which stimulates the growth of heterotrophic bacteria that consume ammonia and nitrite, the main waste products of fish and shrimp metabolism. The bacteria form aggregates with other microorganisms and organic matter, creating bioflocs that can be eaten by fish and shrimp. The bioflocs also provide oxygen, vitamins, minerals, and enzymes to the cultured animals. By reducing the nitrogen load in the water, BFT minimizes the need for water exchange and prevents eutrophication and pollution of the environment.
BIOFLOC TECHNOLOGY A PRACTICAL HANDBOOK Yoram Avnimelech.pdf
What are the Benefits of Biofloc Technology?
Biofloc technology offers several benefits for aquaculture, such as:
Increasing productivity and profitability: BFT can increase the biomass yield and feed conversion ratio of fish and shrimp, as well as reduce the feed cost and dependence on fish meal. BFT can also enable higher stocking densities and shorter culture cycles.
Improving water quality and biosecurity: BFT can reduce the levels of ammonia, nitrite, nitrate, and phosphorus in the water, as well as lower the pH and turbidity. BFT can also enhance the immune system and disease resistance of fish and shrimp, as well as prevent the introduction of pathogens and parasites from external sources.
Reducing environmental impact: BFT can reduce the water consumption and discharge of aquaculture systems, as well as recycle waste nutrients into valuable biomass. BFT can also mitigate greenhouse gas emissions and carbon footprint of aquaculture.
How to Learn More About Biofloc Technology?
If you are interested in learning more about biofloc technology and how to apply it in your aquaculture system, you can read the book "Biofloc Technology - A Practical Guide Book" by Dr. Yoram Avnimelech[^1^] [^2^]. The book covers the principles, design, operation, management, and economics of BFT, as well as provides case studies and examples from different countries and species. The book is available in PDF format online[^3^].
Biofloc technology is a promising innovation that can revolutionize aquaculture and make it more sustainable, efficient, and profitable. By reading this book, you can gain valuable knowledge and skills to implement BFT in your own farm or business.
What are the Challenges of Biofloc Technology?
Biofloc technology is not without its challenges and limitations. Some of the main drawbacks of BFT are:
Managing suspended solids: The accumulation of bioflocs and organic matter in the water can increase the total suspended solids (TSS) and chemical oxygen demand (COD) levels, which can affect the oxygen availability, light penetration, and water clarity. High TSS and COD can also impair the gill function, digestion, and growth of fish and shrimp, as well as increase the risk of bacterial infections and inflammatory responses. Therefore, producers need to monitor and control the TSS and COD levels by using mechanical filters, settling tanks, or water exchange.
Understanding microbial dynamics: The composition and function of the microbial community in biofloc systems are complex and variable, depending on factors such as water quality, feed input, carbon source, aeration, temperature, salinity, pH, and species cultured. The interactions between different microorganisms and between microorganisms and cultured animals are not well understood. This makes it difficult to predict and manipulate the biofloc system to achieve optimal performance and stability. More research is needed to identify and characterize the key microorganisms involved in BFT and their roles in bioremediation and health benefits.
Adapting to different species: Biofloc technology is more suitable for some species than others, depending on their feeding habits, digestive capacity, tolerance to high TSS and COD, and susceptibility to diseases. For example, shrimp are more adapted to BFT than fish because they can filter feed on bioflocs, have a lower oxygen demand, and are less sensitive to high TSS. However, some fish species such as tilapia, catfish, carp, and pangasius can also perform well in BFT if managed properly. Other fish species such as salmon, trout, seabass, and seabream may not be compatible with BFT because they require clear water, high oxygen levels, and low TSS.
How to Improve Biofloc Technology?
One of the ways to improve biofloc technology is to adopt a compartmental design that separates the production unit from the biofloc unit. This allows producers to better control the water quality parameters such as TSS, COD, pH, dissolved oxygen, ammonia, nitrite, nitrate, and phosphorus in each unit. The production unit is where the fish or shrimp are cultured in clear water with minimal bioflocs. The biofloc unit is where the heterotrophic bacteria are grown in high-density with a carbon source. The water is circulated between the two units using pumps and pipes. The biofloc unit acts as a bioreactor that removes nitrogenous wastes from the production unit and produces microbial biomass that can be harvested and fed back to the fish or shrimp in the production unit.
This compartmental design has several advantages over the conventional BFT system:
It reduces the stress and disease risk for fish or shrimp by providing clear water with optimal oxygen levels and low TSS.
It increases the efficiency and productivity of biofloc production by providing optimal conditions for bacterial growth such as high C:N ratio, high aeration, and high pH.
It allows producers to adjust the quantity and quality of bioflocs according to the nutritional needs of fish or shrimp by manipulating the carbon source type and concentration.
It reduces the energy consumption and operational cost by using less aeration and filtration equipment.
Biofloc technology is a promising innovation that can revolutionize aquaculture and make it more sustainable, efficient, and profitable. By reading this article, you can gain valuable knowledge and skills to implement BFT in your own farm or business. 0efd9a6b88