Coral & Sponge Supplements Seachem Reef Phytoplankton 0 Review(s)  £17.58 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 invertebrate diet. Size ranges from 1-20 μm to feed a broad range of marine aquarium filter feeders and invertebrates. Add to cart