Variations in chromophoric dissolved organic matter and its influence on the use of pigment-specific fluorimeters in the Great Lakes

►Effect of chromophoric dissolved organic matter on a fluorimeter was assessed. ►Used up to three FluoroProbes on Lakes Ontario and Huron in spring and summer. ►Individual FluoroProbes are not equally accurate. ►Differences in CDOM correction factors exist between seasons and lake strata.