The dataset presents 5- or 15-minute data for turbidity and Fluorescent Dissolved Organic Matter (FDOM) measured by in-stream sensors at the USGS gage Río Icacos near Naguabo (50075000), Luquillo Experimental Forest, Puerto Rico. The measurement period was 10 March, 2017 to 1 March, 2019. The USGS sensors were co-located with sensors for nitrate and specific conductance operated by University of New Hampshire (UNH), and these datasets are all used in the accompanying publication. A 4-month gap in turbidity in 2018 was mostly filled by UNH data, using a relation between USGS turbidity and co-located UNH turbidity when both sensors were operating. The main metric used in the journal paper was the ratio of coefficient of variation (CV) of concentration (of FDOM, turbidity, nitrate, and specific conductance) to CV of stream discharge over a moving 30-day window, and the main analysis was how this ratio responded to variations in climatic forcing.