(a) Biolog phenotype microarrays were run using an Omnilog instrument (Biolog Inc., Hayward, USA) as previously described (Chaiboonchoe et al., 2014). In total, 380 substrate utilization assays for carbon sources (PM01 and PM02 plates), 95 substrate utilization assays for nitrogen sources (PM03 plate), 59 nutrient utilization assays for phosphorus sources, and 35 nutrient utilization assays for sulfur sources (PM04 plate), along with peptide nitrogen sources (PM06-08 plates) were performed (Dataset 2). All microplates were incubated at 25°C for up to 8 days, and the dye color change (in the form of absorbance) was read with the Omnilog system every 15 min. As the Omnilog instrument does not provide a source of continuous light during incubation, the algae are assumed to be carrying out heterotrophic respiration. In addition, a marked increase in the chlorophyll a content and total cell count was confirmed for wells with suggested growth. Kinetic curves were plotted from the raw data in the form of heatmaps, and statistical analysis was carried out to visualize the metabolic properties and generate Omnilog values. Heatmap density correlates to Omnilog-registered color density. In addition to the dye color change, Omnilog also registers color change resulting from the accumulation of other pigments, including chlorophyll a. Thus, growth is displayed as cumulative color change density. (b) Extraction and analysis by gas chromatography coupled with mass spectrometry was performed as described in Lisec et al. (2006). The color scale corresponds to chromatogram peak areas reported in the GC-MS results in Dataset 2. Significant increase of diverse carbon compounds was observed in Chloroidium sp. UTEX 3007 (Cm) as compared to Chlamydomonas reinhardtii (Cre), and vice versa for nitrogen compounds. These differences may reflect acclimatization to their respective habitats and lifestyles.