1. Reference articles
  2. Conductivity (Electrical Conductivity, Parts Per Million, Total Dissolved Solids)

My nutrient readings are inaccurate, why?

Conductivity meters like our Bluelab Truncheon Meter do not require calibration (as this is saved into the meter during manufacturing) - they just need to be kept clean. 


Nutrient solutions or salts can build up on your conductivity probe face - if this build up is not cleaned from the probe face, then what you would start to see as a result is a reading that is lower then you would expect.


To be safe, we recommend testing and cleaning your meter at least once every month. To see information about cleaning your conductivity probe, click here.


Other factors that can affect your nutrient reading include:

  • Temperature: errors in reading can occur if the solution is much hotter or cooler than the conductivity probe tip of the meter
  • The nutrient solution in use: whether the composition is made of organic or inorganic materials
  • Brand of conductivity 'test' solution in use: always use Bluelab solutions with Bluelab meters to ensure accuracy