BIOFLOC TECHNOLOGY: PROVEN AND POTENTIOAL ADVANTAGES TOWARD FUTURE INTEGRATED AQUACULTURE.

The aquaculture industry struggles to exist in light of low  product prices, increasing costs of inputs and constrains due to environmental, water and land limitations.

Intensive aquaculture systems are relevant to efficiently produce fish and shrimp. However, an intrinsic problem of these systems is the rapid accumulation of feed residues, organic matter and toxic inorganic nitrogen species. Biofloc technology (BFT) systems is a practical solution. Water treatment is based upon developing and controlling heterotrophic bacteria within the culture component, in tandem with nitrifying bacteria and algae. Feed nutrients are recycled, doubling the utilization of protein and raising feed utilization.

The basic concept of BFT is controlling the pond as an integrated system, not separately treating water quality, fish production, zooplankton, disease etc. The bioflocs are an ecological niche containing bacteria, algae, protozoa and zoo-plankton, fed with feed residues and recycling the feed within this niche. Fish feed the bioflocs and harvest them. Bioflocs were shown to improve the immunity of fish and shrimp toward diseases.

Feeding on bioflocs implies economical, natural feed additives and fish health considerations. Presently, research is directed to select biofloc features that provide better health immunity and nutritional values. An intensive direction of research is directed on the search for efficient microbial communities, toward such communities that will optimize cultured animals growth, increase immunity against pathogens and improve nutritive values of the harvested fish.

Another development, to be discussed in a separate presentation, is to develop methodology easing the adsorption of biofloc technology for family farms. We hope this direction will ease intensive aquaculture assimilation in Africa.