Biofloc technology: An innovative approach to zero-water exchange and tentative zero-feed system: A review

Abstract

The intensification of aquaculture since last decade increased at a greater pace to increase per unit production. Likewise, several techniques have been developed over the years while leaving a scope of improvement either inefficiency or production-wise. Limited available resources viz. Land and water, increasing feed cost, diseases and waste management are a serious problem in the current scenario of aquaculture. The developed waste due to vivid inputs (feed, fertilizers, etc.) contains a high concentration of metabolites, fecal matter and unutilized feed, which leads to water quality deterioration. Biofloc technology is proven as zero water exchange and cut down the feed cost-efficiently. Therefore, biofloc can be considered as, sustainable, environment-friendly and cost-effective technology which can be used to develop a zero water exchange culture system to avoid the problem of waste generation and discharge. In this techniques, maintenance of high levels of microbial floc in suspension using constant aeration and addition of carbohydrates to allow aerobic decomposition of the organic material, which stimulates the growth of heterotrophic bacteria and uptake nitrogen from water and in turn produces microbial proteins which are utilized as food sources by fish or shrimp. BFT is having several advantages over the traditional culture system. It is robust, easy to operate, more profitable and economically feasible.