Hanna Instruments

- Check your cuvettes for scratches before each measurement, these scratches can harbor residue from previous samples and thus affect the new sample.

- Always check the expiration dates of your reagents. Reagents that are past their expiration date will no longer have the same

- Wash out your cuvettes with demineralized water after each sample.

- Always respect the reaction time required before reading the result. Each measured parameter has its reaction time.

- Always remove fingerprints from the cuvettes before placing them in the measuring device.

- Always keep in mind the temperature of the water. We recommend room temperature to take your measurements. Do make sure the pool water does not exceed 32°C and spa water does not exceed 37°C.

- Always take your sample at least 30cm below the water surface. Make sure not to take your sample near a jet stream.

Incorrect values can be due to several factors. Below we have provided a small list of things to watch for when taking a measurement.
- Check your cuvettes for scratches before each measurement, these scratches can harbor residue from previous samples and thus affect the new sample.
- Always check the expiration dates of your reagents. Reagents that are past their expiration date will no longer be the same
- Wash out your cuvettes with demineralized water after each sample.
- Always respect the reaction time required before reading the result. Each measured parameter has its reaction time.
- Always remove fingerprints from the cuvettes before placing them in the measuring device.
- Always keep in mind the temperature of the water. We recommend room temperature to perform your measurements. Make sure the pool water does not exceed 32°C and spa water does not exceed 37°C.
- Always take your sample at least 30cm below the water surface. Make sure not to take your sample near a jet stream.

If you have purchased a new device, you should always remove the plastic partition that protects the batteries. Sometimes you have to unscrew the top of the device. If you still have problems with your device, please contact us via the chat at the bottom right or via the contact page.