Plankton
Tiny organisms that produce oxygen and form the basis of the marine food web.

 

Sea cucumbers
They clean the ocean floor by filtering sediments and recycling nutrients.

 

Seagrass crabs
Small helpers that maintain seagrass meadows and reduce algae growth.

 

Diatoms
Microscopic algae that bind CO₂ and improve water quality.

 

Wrasses
They keep coral reefs healthy by controlling algae.