In a food chain what would come first animal plankton or plant plankton?

In a food chain, plant plankton, also known as phytoplankton, comes first as they are primary producers that convert sunlight into energy through photosynthesis. Animal plankton, or zooplankton, are consumers that feed on phytoplankton. Thus, phytoplankton serves as the foundational level of the food chain, supporting higher trophic levels, including zooplankton and other marine animals.