Two studies were conducted in laboratory (E1 and E2) with clownfish juveniles Amphiprion ocellaris in which the survival, growth, body colour and total carotenoid content in the skin were evaluated. In E1, diets supplemented with one of three levels of lutein or astaxanthin (0.5%, 1% and 1.5%) were evaluated; and, subsequently, in E2, two background colours were used in the fish tanks (black/white), which included two different light spectrums (white/red). The survival and growth rate of the fish in both studies were similar irrespective of the treatment. The fish fed the diets supplemented with 0.5% and 1% astaxanthin (E1) exhibited an intense red pigment and a significantly superior (p < 0.05) total carotenoid concentration in skin compared to the other treatments. In E2, an intense red pigmentation and well-defined black bands were observed in fish kept in black background tanks, whereas fish kept in tanks with white background had a yellowish hue and barely visible bands. In contrast, the light spectra did not have an effect on body pigmentation. Based on the results, it was concluded that the body colour of the clownfish depends on the carotenoid source in the diet and the colour of the culture system rather than the light spectra. It is, therefore, recommended that a minimum of 0.5% astaxanthin is included in the diet and that the fish are kept in tanks with a black background, to maintain the intense red coloration that is characteristic of the species.