The frequency and severity of coral bleaching events have increased in recent decades. Regionally, human-attributed nutrient pollution, particularly nitrate, has increased in coastal areas due to inflow from rivers and groundwater. The combined effects of increased nitrate concentrations with high temperature or high light on bleaching events and reactive oxygen species levels (ROS) were tested. Coral fragments of Montiporci digitata were incubated for 3 and 6 days at different light intensities (200 and 600 μmol m-2 s-1), temperatures (27 and 32 °c), and nitrate concentrations (