To investigate dietary calcium requirement of bighead carp (Aristichthys nobilis), six purified diets were formulated to contain different concentrations (0.09% (control), 0.43%, 0.76%, 1.12%, 1.44%, and 1.79% dry diets). Each diet was hand-fed triplicate 30 fish with an average initial body weight (3.31 ± 0.09 g) for 60 days. The results showed that gain (WG) specific growth rate (SGR) signifi...