The rosy barbs used in the experiment
were obtained from a grower who had reared the
fish in green water. Because the fish has bright
coloration when obtained, they were held for 1
mo. in shaded, algae-free aquaria before the trials
began. The rosy barbs were treated with one of
four diets: a flake with no added carotenoid
source, a flake with traditional carotenoids, a flake
incorporating 0.5% Spirulina and 0.4%
Haematococcus, and a flake with 1.5% Spirulina
and 1.0% Haematococcus. Kissing gouramis and
24K mollies were also obtained from growers but
were from shaded aquaria containing no algae and
they received the same diets as the rosy barbs.