What is biofloc?
This technology is based on the promotion of a microorganism population composed by autotrophs organisms able to produce their own food using light (photosynthesis; photoautotrophs) or chemical energy (chemosynthesis; chemoautotrophs), as well as heterotrophic organisms, which require organic carbon. Therefore, BFT will be able to reuse the organic carbon waste from rearing animals or aquafeeds into valuable microbial biomass. Additionally, autotrophs organisms will be able to oxide the inorganic nitrogen (ammonium (NH4+) and nitrite (NO2–)) into nontoxic element (NO3–) through the nitrification process. Both processes will allow maintain the water quality conditions to culture aquaculture species with minimum water requirements, even under a super- or intensive production. Besides, this biomass can be subsequently used on-site as a nourishing food source for the rearing animals.
Moreover, the symbiotic relationship between autotrophs and heterotroph organisms can colonize the intestinal track of the rearing animals, enhancing nutrient assimilation and acting as probiotic/prebiotic agents with immune-stimulating effects. In crustaceans, activation of innate immunity relies on cellular and humoral components, while in fish, on non-specific immune systems have been reported
How will we work with it?
The heterotrophic nitrification of the organic nitrogen into microbial fraction allows not only a zero or minimal water exchange, meeting clearly with the objective of sustainable use and protection of water and marine resources, but also reducing the eutrophication thanks to a lower nitrate (NO3–) accumulation into the water system. This low water dependency will allow aquaculture farms to be near consumers, reducing the environmental impact and offering a fresh zero-kilometer product. Moreover, compared to other sustainable aquaculture systems such as aquaponia, BFT allows intensive production, and enables its implementation into Integrated Multitrophic Aquaculture Systems (IMTA-BFT) or hydroponic systems (FlocPonics), enhancing even more its productivity. Finally, it provides a high biosecurity thanks to the lack of communication between tanks and increased resistance to pathogen outbreaks
Where is our research going?
BFT is still a relatively new technology and, due to its complexity, still needs to be better understood, mainly under intensive conditions and be adapted to European consumption patterns. BFT operates as a self-contained ecosystem, where numerous interrelated factors exert simultaneous influence on its performance. Consequently, BFT demands an interdisciplinary approach (from microbiology to animal welfare management) to gain knowledge about its management, microorganism composition and optimal feeding, intending to achieve the best growth performance without losing economic profitability, product quality, and animal welfare
Impact
