That's an excellent question, Jonny. We recommend calibrating your Hanna HI9142 before each use. You can find the necessary solution on our website here: www.itm.com/product/hanna-instruments-hi7040l-zero-oxygen-solution-500-ml. Hope this helps. If you have more questions, don’t be shy to contact us.
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How often do you recommend a full calibration of the unit?
That's an excellent question, Jonny. We recommend calibrating your Hanna HI9142 before each use. You can find the necessary solution on our website here: www.itm.com/product/hanna-instruments-hi7040l-zero-oxygen-solution-500-ml. Hope this helps. If you have more questions, don’t be shy to contact us.