Does a plankston float on the ocean or in the ocean?

Question

Does a plankston float on the ocean or in the ocean?

Answer 1

Plankton floats in the ocean, mostly near the surface. If it floated like a cork, the top parts would dry out and the creatures would die.

What happens is the plant plankton (phytoplankton) needs to be near the surface to get sunlight for photosynthesis, and the animal plankton (zooplankton) needs to be near the phytoplankton to eat it.

Some of the zooplankton is larval fish and other creatures -- as soon as it grows large enough to go after bigger stuff, it "settles out" towards the middle depths or bottom.

Anyway, there's a pretty good explanation on wikipedia.