Dr. G's Live Phytoplankton is a blend of freshly Aquacultured and packed alive micro algae, thus the perfect nutrition for Corals, FilterFeeders, Invertebrates, Zooplankton and small fish. Feather duster worms, soft corals, clams, tunicates, zooplankton and other reef inhabitants can't survive without Live Phytoplankton. Our blend contains motile and free floating Live Phytoplankton with no preservatives or additives.