Best way to increase PH in my tank without affecting other parameters?

[Preyou]

Good day all. Hoping for some additional insight into my situation. I am currently running an SPS dominated reef with a Calcium Reactor. My alk typically runs around 10dkh, my calcium is 450, my mag is 1250, and phosphate is .05. My PH sweeps daily from a low of 7.4 to a high of 7.8 but the average is 7.54. I have tried adding a CO2 scrubber to my skimmer, but there was no appreciable difference in the PH numbers. I typically only run the skimmer for 8 hours a day due to a light bioload and I have set these hours to coincide with the daily dip in PH. I am considering the addition of kalkwasser to my top off water, but I am concerned with the additional Ca and alk that this will supply. Suggestions are appreciated.

 

[homer1475]

How are you checking PH? Have you tried the water in a cup outside, then measuring the PH method to see if it's high Co2 causing the low PH?

 

[Preyou]

I have not, I plan on doing that this evening. I use my Apex to monitor the PH and recently replaced/calibrated the probe.

 

[Randy Holmes-Farley Verified Community Expert]

I don't believe that pH 7.4 is accurate. It is too low to seem real. pH 7.7 is about the low end of real values. maybe 7.6 in extreme high CO2 households.

I'd get the measurement confirmed before worrying about it.

Try measuring in a cup away from the tank. Controllers sometimes seem to have issues with proper pH measurement. Try new calibration fluids and read the fluids again after calibration.

This has more:

pH And The Reef Aquarium
http://www.reefedition.com/ph-and-the-reef-aquarium/

 

[Preyou]

Thanks for the input Randy. I actually have a new Apex running in parallel on this system and had not yet installed the ph probe. After I saw your message, I installed and calibrated the probe. The probe gave me a reading of 8.07.

I then recalibrated the probe on the old Apex and have come to the conclusion that I have a bad probe. I will be replacing that probe before I move the Apex to my nano.

I will provide updated ph numbers in a couple of days.

Thanks again!

 

[Preyou]

I don't believe that pH 7.4 is accurate. It is too low to seem real. pH 7.7 is about the low end of real values. maybe 7.6 in extreme high CO2 households.

I'd get the measurement confirmed before worrying about it.

Try measuring in a cup away from the tank. Controllers sometimes seem to have issues with proper pH measurement. Try new calibration fluids and read the fluids again after calibration.

This has more:

pH And The Reef Aquarium
http://www.reefedition.com/ph-and-the-reef-aquarium/

Looks like the actual numbers are 7.9 on the low end and 8.1 at the peak. I guess things weren't as bad as I thought.