A food chain is a linear network in the food web that starts from a producer organism such as phytoplankton and ends at an apex predator species, detrivores, or decomposer species.
It is a linear sequence that gives accurate information regarding the flow of energy from one species to the other.
The food chain is very important for the balance of the ecosystem.
Aquatic food chain:
The food chain existing in the aquatic ecosystem is called an aquatic food chain.
It starts with primary producers such as phytoplankton and then zooplankton which feeds on them.
Zooplanktons further get eaten by the small fishes, which in turn are eaten by big fishes and predators.
Phytoplankton—> Zooplankton —> Small fish—> Big Fish—> Top predator