Tank colours do not change the effects of extreme temperatures on the productive parameters, but skeletal deformities of golden trevally

The objective of this study was to evaluate how the tank colours may change the effects of extreme temperature on the survival, growth, and quality of juvenile golden trevally ( Gnathanodon speciosus ). The experiment was set up with fifteen treatments of five tank colours (blue, red, yellow, grey, and white) and three temperatures (30 ℃ , 32 ℃ , 34 ℃ ) with three replications. Fish performance was assessed for four weeks. The results showed that tank colours and elevated temperatures affected the quality of golden trevally juveniles. The survival and growth rate of fish tend to decrease gradually, but the deformation rate of fish tended to increase in the order of tank colours: red, yellow > grey, blue, and white. The growth and survival rate of fish gradually decreased when the rearing temperature increased from 30 ℃ to 34 ℃ and this effect was independent of tank colors. Importantly, the deformation rate increased under elevated temperature, particularly in blue and white tanks with potential long-term effects. It is, therefore, not recommended to use blue and white tanks for rearing the golden trevally juveniles, particularly during extremely high temperatures from heatwave events.