The carotenoids used in the diets were selected to
include a range of carotenoids found in natural algal diets
of sea urchins (Diets 2, 3, 4, 6) and from commercially
available carotenoids not usually consumed by P. lividus
(Diet 5). Diet 6 was provided as spray-dried D. bardawil
powder (Nature Beta Technologies Ltd., Eilat, Israel).