Cleaning Conductivity Probe?

[SteveMM62Reef]

Is there anyway of cleaning a Conductivity Probe. The Probe is on a Fluval G-3 Filter. Over the years the Salinity Readings have dropped to the point it is useless. I used it as an emergency alert, for my salinity. I’ve tried a Soft Tooth Brush and Citric Acid. The Citric Acid may have not been strong enough or applied long enough. Want to get a feedback from anyone else who has cleaned any conductivity probes. BTW They are not replaceable, according to Fluval.

 

[Sral]

Sadly the Online Manual only mentions cleaning with soft jets of water and nothing about calibration. Is there a menu option for EC calibration ?

I found this online Forum about a Pool chlorinator with titanium electrodes. That one should be soaked for 2h in vinegar and doused with water to clean, according to its manual. If the electrodes are "shot" anyway and nobody mentions anything else, you might try this.

If that doesn't work you can try more abrasive methods, like toothpaste. That should be the absolutely last resort however, since this might roughen up the surface, possibly leading to skewed readings and more dirt buildup over time.

 

[SteveMM62Reef]

Update; on my last complete G3 tear down. I made up One Tablespoon of Citric Acid to One Cup Hot Tap Water. Mixed it till Citric Acid was dissolved. Tore off a piece of paper towel, placed it over the Probe Points, and repeatedly soaked the paper towel in the Citric Acid Solution, for about a half hour. Now registers correctly at 34ppt. BTW Vinegar did nothing in the past. Also I soaked the impeller in the Citric Acid, but it‘s time for a new impeller.