JBL ProAquaTest CO2 Plus PH Permanent Water Test Kit

ProAquaTest CO2 Plus PH Permanent Water Test Kit contents: 1 x CO2 and pH Permanent Test Kit, 2 Reagents and adhesive colour chart. How exactly does the test work?The CO2 dissolved in the aquarium water diffuses in the container of the permanent test, passes into the air column containing the indicator liquid and then dissolves in the liquid.

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