Sluggish pH

[Rolliad]

Hey everyone! I have an issue that I'm hoping folks can help with!

My pH is sluggish the last like 9 days or so(7.9) and I don't understand why. I had been sitting at 8.25 and then it dove overnight (7.4) because my Co2 scrubber media needed to be changed. I changed it once I woke up, and then it came up to ~7.75. I recalibrated my probes on my Hydros iV and it didn't budge. Then my alk dove from 9 to 6.5 over the course of that day.

I started dosing my tank with Brightwell Alkalin8.3 and over the course of several days my alk came back up to 9. However, my pH remains at 7.9. I've had the windows open for 4 days straight and it just wont budge.

Any thoughts on what might be causing that? On how to remedy?

Thanks!

 

[EeyoreIsMySpiritAnimal]

7.9 is not necessarily bad

 

[BiggestE22]

I seriously doubt it dropped to 6.5. There is a probe issue.