“…The estimated requirement for H. fossilis (5.24–5.68 mg/kg diet) is apparently lower than the requirements reported for various fish such as Atlantic salmon (8.5–13.7 mg/kg, Lorentzen, Maage, & Julshamn, ); beluga (10.3 mg/kg, Mohseni et al, ); Russian sturgeon (7–8 mg/kg, Wang et al, ), comparable to spotted snakehead (6.66–6.78 mg/kg, Hameid et al, ); channel catfish (5 mg/kg, Gatlin & Wilson, ) and higher than reported for rainbow trout and common carp (3 mg/kg, Ogino & Yang, ); grouper (2–3 mg/kg, Lin et al, ); red sea bream (2 mg/kg, El‐Basuini et al, ); yellow catfish (3.13–4.24 mg/kg, Tan et al, ); and grass carp (4.70–4.95 mg/kg, Tang et al, ). These variations in the dietary copper requirements may also be the result of the differences in the type of diets, stage and species of fish, form of supplemented copper, rearing water copper concentration, selection of various response indicators, experimental design, tenure and different statistical models used.…”