Biguanide in Water - DIY Test

Biguanide, an alternative to chlorine in swimming pools

Biguanide is a class of chemical compounds consisting of molecules with two guanidine groups. These compounds are often used in various fields, including medicine as antidiabetic agents (such as metformin) and disinfection as antiseptic or disinfectant agents. Specifically, in swimming pool water disinfection, biguanide (often in the form of polyhexamethylene biguanide or PHMB) is used as an alternative to chlorine to keep water clean and healthy. It works by eliminating bacteria, algae, and other unwanted organisms in the water.

The benefits of biguanide

Used as an alternative to chlorine in private swimming pools, biguanide offers several benefits:

1. Less irritating than chlorine: compared with chlorine, biguanide is less irritating to swimmers' skin and eyes.
2. Less odor and taste: biguanide does not produce chlorine's strong odor or distinctive taste. This makes swimming more enjoyable.
3. Highly stable: it is more stable than chlorine in water, meaning it stays active longer without requiring such frequent additions. This can reduce the maintenance needed to preserve pool water quality.
4. Effective against bacteria and algae: biguanide is an effective disinfectant that eliminates bacteria, algae, and other contaminants from pool water. It offers protection similar to chlorine by keeping water clean and healthy for swimmers.
5. Tolerates a wide range of conditions: it is effective over a wider pH range than chlorine, meaning it can remain effective as pool water pH varies.

Maintaining a pool treated with biguanide

Although biguanide generally requires less maintenance than chlorine, it still requires regular water quality monitoring and proper maintenance of the pool's filtration and circulation system.

To maintain an effective concentration of biguanide in pool water, it is important to test the biguanide level regularly using dedicated test kits. The biguanide dosage must be adjusted based on test results and pool conditions.

Note that biguanide is incompatible with chlorine, bromine, copper, and bronze.

How does the biguanide water test work with the eXact Micro 20 photometer?

This kit contains 50 strips (packaged in bags of 12) treated with a reagent specifically designed to test for biguanide.

It is important to note that biguanide analysis with this kit can only be performed with the eXact Micro 20 photometer. Other photometers in the eXact range do not have the correct wavelength for this test and would produce an incorrect result.

Test procedure

	Remove a strip from the container before starting the test. Leave it in a dry, easily accessible place, and close the container immediately.
	Turn on the photometer by pressing the ON/ZERO button. The screen will show all indicators, then the selected menu, then the most recent results.
	Press the SELECT button repeatedly to choose the group: the biguanide test belongs to group 3. Then press the MENU button repeatedly to select the test parameters: bG. (You will find all this information in a table in the user manual supplied with the device.
	Rinse the test cell at least 3 times with the water you will be testing (to reduce the risk of cross-contamination from your previous test). Finally, fill the small cell completely with the water to be tested.
	Press the ON/ZERO button. The cursor will move across the screen before it displays 0.00PM. This indicates that the sample is ready to be tested.
	Dip the appropriate strip into the small cell and immediately press the READ button. This will start a countdown. During the countdown, gently move the strip back and forth (about 1 back-and-forth motion per second). As soon as the "1" disappears from the screen, remove the strip.
	The cursor will move across the screen while the photometer prepares the test results. Record the value displayed for the parameter. This value is automatically saved in the MENU, and if you use the exact iDip app, the results will be saved in its "RESULTS" section. After the test, rinse the cell and clean it with the small brush.