Need Help for Interpreting pH Results

[rhpmiller]

Been using a Hanna pH checker for over a year and have regularly been getting readings of 8.6+ (8.6 flashing on screen). If I put 20-30 mL (have a 20g nano) of some white vinegar in the tank, usually will bring the reading down to 8.3 or 8.2.

However, recently got the Apex A3 Pro and have had the pH probe in there and it's been rolling between 7.5-8 each day, which would be quite a difference from the 8.6+ from Hanna. So that caused me to go get an API and Salifert pH test to try and get a better sample of results.

Would love the forum's help in 1) seeing if you're seeing what I am in the color tests, and 2) has anyone had issues with calibrating their Apex pH probe?

I'm seeing about an 8.2 in both of the tests below. What are you reading?

Appreciate the help!

 

[Troylee]

I’m having the same problem with my apex probe all of the sudden after the update.. I can’t even get it to calibrate correctly so I just ordered a new one.. I’d go off salifert their tests are pretty solid.

 

[jda]

The best way to check pH is to get a cheap pH pen and some calibration fluid off of amazon. The are pretty accurate if you calibrate them right and do not use the calibration fluid much after the expiration date. They are easier, and maybe even cheaper, than using a color indicating pH test kit.