Chlorophyll a is assumed to be directly proportional to the concentration of phytoplanktonic algal biomass.
chla=α0​∗algae 7:3.1.1
where chla is the chlorophyll a concentration (μg chla/L), α0​ is the ratio of chlorophyll a to algal biomass (μg chla/mg alg), and algae is the algal biomass concentration (mg alg/L).