: Small organisms like Rotifers , Copepods , and Brine Shrimp that feed on phytoplankton. Where to Buy:

: The "plants" of the ocean. Common species include Nannochloropsis , Tetraselmis , and Isochrysis .

Aquarists buy plankton to feed corals, filter feeders, and small fish like Mandarins. It is generally categorized into two types: