A method for developing an algorithm for quantifying the hydrocarbon content of aqueous media includes: a) irradiating aqueous test samples containing hydrocarbons and particulates with light so that fluorescent emissions and scattered light signals are emitted from the test samples; b) detecting fluorescent emissions and the scattered light signals emitted from the test samples; c) generating first data signals representing the intensities of the fluorescent emissions, and second data signals representing the intensities and scatter angles of the second data signals; d) storing representations of the first and second data signals to create a data set; e) dividing the data set into training, test, and validation data sets; f) selecting input parameters from the data set; g) defining and training a neural network having hidden node using the training and the test data sets; and h) validating the neural network using the validation data set.