Cellular carbon (C) and nitrogen (N) data of the Karlodinium veneficum growth experiment conducted in the Horn Point Laboratory between June 2021- January 2022.

Using a multifactorial design, we studied the interactive effects of temperature (15, 20, 25, 28 and 30 0C), salinity (5, 10, 15, 20 and 30) and light (low-100 and high-300 μmol photons m−2 s−1) on growth, thermal niche properties and cellular carbon (C) and nitrogen (N) of the toxic dinoflagellate, Karlodinium veneficum, originated from the Chesapeake Bay. Here we report the daily growth data measured as raw fluorescence at each experimental combination in quadruplicates and the C and N cell quota data measured in the final samples for each experimental combination in duplicates.