Evaluation of Various Sources of Bacteria on Biofloc Productivity

Abstract

Biofloc technology is a new alternative in addressing water quality problems in aquaculture which is adapted from conventional domestic waste processing techniques. The main principle applied in this technology is water quality management which is based on the ability of heterotrophic bacteria to utilize organic and inorganic N in water. In a balanced C and N condition in water, heterotrophic bacteria which will utilize N, both in organic and inorganic form, are present in water for the formation of biomass so that the concentration of N in water is reduced. Several types of bacteria that are often used in biofloc are Bacillus sp., Bacillus subtilis, Pseudomonas sp., Bacillus lichenoformis, Bacillus pumilus; Lactobacillus sp.; Bacillus megaterium .  Microbes play key role in the biofloc systems. Microbes associated with floc after consumption help to improve digestion, reduces FCR reduces dietary protein level and heterotrophic bacteria, which together probiotic bacteria, inhibit the development of potential pathogen bacteria. With biofloc there are some improves in different aspects during culture like higher growth rates, increased survival, improved water quality, reduced amount of water used and decrease in diseases. Thus, role of microorganisms is important in biofloc system; therefore, it is necessary to carry out more studies related to identification of microbes that can be present in biofloc systems.