Megaplankton > 20 cm
(eg jellyfish!),
Macroplankton 2→20cm
Mesoplankton 0.2→20mm
Microplankton 20→200µm
Nanoplankton 2→20 µm,
Picoplankton 0.2→2 µm
Femtoplankton< 0.2 µm

Note – having recently visited Phillip Island new exhibit “Antarctica”, as oceans are main engines of life, it’s curious to check that distribution is less even than you might think, cool Antarctic waters are critical

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