Seachem reef phytoplankton is a concentrated blend of green and brown marine phytoplankton designed to provide the essential fatty acids proteins vitamins amino acids with biological carotenoids for a balanced invertebrate dietr r particle size ranges from 1 20microm to feed a broad range of tropical marine aquarium filter feeders and invertebratesr contains a natural source of carotenoids which provides essential proteins as well as a more bio available source of pigmentation when com