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Fluoride Water Testing Sensor

What is fluoride testing?

Fluoride testing is carried out to investigate fluoride levels in water. Fluoride is a naturally occurring ionic compound (or salt) that is found in low levels in most bodies of water. The concentration of fluoride in water is affected by: climate, geology, contact with fluoride minerals and groundwater chemical composition. Fluoride is dissolved into water from the surrounding soils and rocks. Some research has shown that water temperature and hardness appears to influence the toxicity of fluoride, but more needs to be done to strengthen this relationship.


In unpolluted ocean waters the natural fluoride level is in the range of 1.3 to 1.4 mg/L. The levels are usually lower in estuarine areas due to dilution by fresh water, unless fluoride pollution is occurring upstream. Measuring fluoride in water is important as fluoride is toxic to humans and aquatic life. Fluoride is accumulated in the hard tissues of fish and shellfish, and then enters the food chain when the organisms are eaten.

Marine organisms can accumulate fluoride even at ambient ocean levels, and this accumulation increases noticeably when there are higher fluoride levels are present. As fluoride moves up the food chain, biomagnification occurs at about 1 order of magnitude per level.

Why measure fluoride levels in water?

One might want to monitor fluoride levels in water to determine the ambient level of fluoride in a water body. Once the base level is known, continued measuring of fluoride in water will allow any pollution to be identified by any spikes in fluoride concentrations. Measuring fluoride in water close to industrial areas, for example aluminium smelting plants, is necessary to carefully monitor the levels of fluoride in drinking water that is produced in water processing plants. High concentrations are dangerous for humans and can cause dental fluorosis, or skeletal fluorosis in extreme cases.


Aquaread’s water fluoride meters

Aquaread’s fluoride meter is just one of the optional ion specific electrodes (ISEs) that is compatible with Aquaread’s multiparameter water testing equipment, Aquaprobes. Fluoride ISEs are sensitive to the concentration of the fluoride ion in aqueous solutions. The solid state sensor doesn’t contain any liquid so can be stored dry, and has a shelf life of more than 1 year.

ISEs are a preferred method of fluoride testing because of fewer interferences than other methods, although electrodes still suffer interference from hydroxide (OH-) ions, which are similar in nature. Our fluoride meters are accurate to +/- 10% of the reading and, depending on the equipment that you choose, can be deployed for long term, unmanned water quality monitoring. Our ISE fluoride sensors are great for measuring fluoride in water within a range of 0 – 1,000mg/L (ppm).

We have three Aquaprobe products that the fluoride meter can be used with. Each Aquaprobe measures a set of standard parameters and comes with the option to add further parameters. All measurements are taken simultaneously, vastly reducing the time required to monitor water quality, especially if you have a large number of sample sites. The Aquaprobe AP-7000 is our latest model and is specifically designed with long term deployment in mind. It has 6 additional sensor ports for ultimate customisation, and has an innovative self cleaning function built in.


The Aquaprobe AP-5000 allows you to add up to 4 additional sensors, yet the whole device is only 55mm wide, so it is portable and perfect for use in the field. The Aquaprobe AP-2000 is our most portable multi parameter probe. In addition to the standard parameters you have the choice of adding one additional ISE and one optical electrode. All Aquaprobes are used with the Aquameter, which records the data and has built-in GPS to geotag each data set. You can also have your data beamed remotely straight to your desk which is ideal for long term fluoride testing, reducing transport costs and generally being more time effective.

Get into monitoring with Aquaread

If you would like any more information about TDS meters and other total dissolved solids testing equipment, or water quality monitoring in general, please Contact Us. Click here to see our product range.