One of the most common uses of a rhodamine dye test is measuring time of travel for surface, ground and waste water. Time of travel refers to the movement of waterborne substances, from one point to another in a stream during steady or gradually varied flow conditions. This form of rhodamine testing involves rhodamine being injected into the water, with the concentration of the dye is measured at other locations downstream using a fluorometer.

The fluorescent properties of rhodamine mean that when it is irradiated with a light of a particular wavelength it emits a light of a higher wavelength. The rhodamine sensor measures the light fluoresced by the rhodamine. The concentration of the dye in the water is relative to the fluorescence, so this measurement gives an accurate indication of the rhodamine levels in the water sample.

A rhodamine sensor works by sending a light beam into the water to be tested, at a fixed wavelength. This wavelength of light excites the dye which subsequently fluoresces at a known wavelength band. The level of excitation measured is proportional to the amount of dye present in the water.

To use Aquaread's rhodamine sensor, first install it into your probe of choice, then perform a full calibration of the using fluorescein dye. Once calibrated it's good to go. Simply put the probe into the body of water, allow the reading to stabilise and take your measurement.

Water rhodamine meters are the ideal solution because they can be left unattended for days or weeks. Our Aquaprobe multiparameter water testing devices are designed for use in the field, and some of the models are designed for long term deployment. Using a fluorometer in-situ eliminates the cost of lab analyses and is suitable for both continuous-flow monitoring or discrete sample analyses.

There are many applications for rhodamine testing. You can use rhodamine dye and fluorometers in surface water, wastewater and groundwater. In surface water you might study irrigation uptake by plants, spill mapping and response and mixing zone identification and characterisation. In wastewater, rhodamine testing is used to monitor sewer overflows and for hydraulic characterisation of wastewater treatment facilities for operations or environmental purposes, for example. For groundwater, you might use a rhodamine sensor to monitor aquifer hydraulics, trace pollution plumes, and tag and trace herbicide migration and dispersion.