Red and green fluorescence of group R3 were highest, whereas red fluorescence of R4 was lowest amongst the groups, but its green fluorescence was as high as
the R3 group. The result demonstrates that the size and chlo- rophyll content of sorted cells corresponds with sorting criteria, i.e. sorted cells of group R1 and R2 had a size of approximately 3 mm, and group R3 10 mm. CAF in each of the groups differed, where group R4, which was low in red fluo- rescence, was successfully sorted based on its GAF. In this study, the CAF of microalgae was used successfully as a biomarker to distinguish and isolate microalgae in natural seawater samples. Using the CAF vs. GAF protocol a diverse taxa of microalgae was isolated. In agreement with previous studies by Tang and Dobbs [8] and Lage et al. [17], the GAF protocol aided in the taxonomic identification of dinoflagel- lates, diatoms, green algae, cyanobacteria, and raphidophytes