S1. pH data of treatments over the 6-day experiment of blank, S. marinoi, and F. pseudonana bottles.

‘Level’ indicates target pCO2 concentration (µatm), ‘pH’ indicates the averaged pH measurement, and ‘sd’ indicates the standard deviations of the pH measurements. Day 0 growth media and Day 6 values are means ± standard deviations of quadruplicate and triplicate measurements. Day 3 values are single measurements. S2. DIC data of treatments over the 6-day experiment of blank, S. marinoi, and F. pseudonana bottles. ‘Level’ indicates target pCO2 concentration (µatm), ‘Carbon Level’ indicates the averaged pCO2 measurement, and ‘sd’ indicates the standard deviations of the pCO2 measurements. Day 0 growth media and Day 6 values are means ± standard deviations of quadruplicate and triplicate measurements. Day 3 values are single measurements. S3. PUA data of treatments over the 6-day experiment of S. marinoi, and F. pseudonana bottles. ‘Level’ indicates target pCO2 concentration (µatm), while ‘Hepta,’ ‘Octa,’ ‘Deca,’ and ‘Total’ indicate the averaged PUA measurements (nmol/μg chlorophyll-a) of heptadienal, octadienal, decadienal, and total PUAs. (ZIP)