Chattonella marina (CMHK) and C. ovata (COHK), previously isolated from Hong Kong waters, South China Sea, at 2002 and 2003, respectively, were provided by the Research Center of Harmful Algae and Marine Biology, Jinan University. Stock non-axenic cultures were maintained at 20 °C, 28 salinity and 100 µmol m−2 s−1 of light intensity with a 12:12 light:dark cycle.

Growth rate (µ) of C. marina or C. ovata was calculated using the following equation:

where C2 and C1 are the cell numbers at the end of the logarithmic phase (t2) and at time zero (t1), respectively [105].