Zooplanktos S Zooplankton by Brightwell Aquatics provides zooplankton and fully-digestible, unhatched eggs ranging in size from 50 - 300-µm. Zooplanktos S is highly-concentrated; ideally-sized for many stony corals, clams, sponges, tunicates, tube worms, larval crustaceans, juvenile fishes, and adult planktivorous and microinvertebrate-predatory fishes. This product is rich in amino acids, fatty acids including omega-3 HUFAs, vitamins, minerals, and carotenoid pigments giving them a natural, bright yellow appearance. It is supplemented with a proprietary amino acid to aid in coloration of invertebrates and fishes. Product does not require refrigeration.