What are 5 first level consumers in an ocean ecosystem?

In an ocean ecosystem, five first-level consumers include zooplankton, small fish like anchovies, krill, sea urchins, and certain types of mollusks such as clams. These organisms primarily feed on primary producers like phytoplankton and marine algae, converting the energy from these producers into forms that higher trophic levels can utilize. They play a crucial role in the marine food web by transferring energy from autotrophs to higher-level consumers.