Control of mortality and diseases as well as to ensure most efficient FCR with optimum weight gains are ever-increasing challenges for profitable aqua farming. Antibiotic growth promoters have been major components in aquaculture nutrition.  Currently, serious concern is being felt regarding the use of antibiotic growth promoters for aquaculture as use of any antibiotic over a period of time have the potential to create a pool of antibiotic resistant bacterial genes in the environment, allowing the pathogenic and non-pathogenic organisms to develop into superbugs causing direct or indirect human health hazards. A ban on usage of antibiotic growth promoters by Marine Products Export Development Authority (MPEDA) and most of the countries importing aquaculture products has intensified the challenges of aqua farming.