In the Limnetic Zone the rate of photosynthesis becomes equal to the rate of respiration. Which is where, net primary production no longer occurs. Life in the limnetic Zone is dominated by floating microorganisms called plankton and actively swimming animals called nekton.
In this ecosystem the producers are planktonic algae.
In the limnetic zone there are primary consumers such as microscopic crustaceans and rotifers - another name for it is the zooplankton. The secondary consumers are swimming insects and fish. These animals usually swim between the littoral and limnetic zones.