This dataset contains measurements of chlorophyll a content, quantified by determining a change in the total pigments of the endosymbionts of the benthic foraminifera Amphistegina lobifera, exposed to electric currents over a one-month period. The data were collected in April 2023, the first of a two-part experiment, using a Tecan Spark plate reader operated with SparkControl v2.3. This dataset provides insights into the effects of electric currents on the physiological responses of the diatom symbionts of Amphistegina lobifera.