Balancing different ratios of C/N in a recirculating aquaculture using feed and molasses for forming Bio-floc and their effects on growth of silver carp and water quality

A completely randomized experimental design was conducted to evaluate the effects of different ratios of C/N 10, 15, 20 through feed and additive molasses on silver carp growth and water quality in a recirculating aquaculture system. The results indicated that with an increase in the ratio of C/N , the growth of fish, FCR and PER significantly improved(P<0.05) . The water quality of water significantly (P<0.05) improved as well. It was concluded that balancing the ratio of C/N can be used as a practical and zero exchange of water method for culture of fish due to bio-floc formation and improving fish growth and reduction of fish metabolites. This method can be introduced as an environmentally and friendly method for culture of carp due to treatment of environmental constrains of water.