Is it Possible for PH to be too high?

[acesfull44]

So I have read the Optimal Parameters thread by Randy Holmes-Farley to understand better what I am worried to be as a potential problem.

This could be a very stupid concern on my part, but I am newer to this hobby, and thought I would ask some more qualified people on here to give me their opinions and feedback.

I added a light to my sump on 11/19 (this may be completely irrelevant), and noticed since that day, my PH readings have been steadily climbing. I would like to hear some thoughts on why this could be happening, if I should be concerned and if so about what? What can be done about this, and should I address it? Thanks in advance for your feedback here.

Apex readings are as of midnight each night:

Nov 20 - 8.14
Nov 21 - 8.24
Nov 22 - 8.34
Nov 23 - 8.43
Nov 24 - 8.58
Nov 25 - 8.59
Nov 26 - 8.75 (10:42 pm central)

 

[ermartin]

lighting can help keep PH stable... Its not the lighting driving it up .. either the device is getting some kind of interference or something else is going on. you should do a manual test

 

[WVReefJunkie]

I agree, do another test for PH.

 

[WVReefJunkie]

Check calibration of the probe. You could also stick it in some fresh water and see if the ph readings change verses what the apex is reading.

 

[JimWelsh]

Also, pay special attention to alkalinity. A steadily increasing pH might be in indication of an ongoing alk overdose.

 

[Pete polyp]

Lighting the sump during the time the lights are on in the display can raise ph. Try lighting the fuge while the lights on the display are off and it should help reduce the swing.

 

[acesfull44]

I agree, do another test for PH.

Check calibration of the probe. You could also stick it in some fresh water and see if the ph readings change verses what the apex is reading.

Also, pay special attention to alkalinity. A steadily increasing pH might be in indication of an ongoing alk overdose.

Lighting the sump during the time the lights are on in the display can raise ph. Try lighting the fuge while the lights on the display are off and it should help reduce the swing.

Thank you all very much for the feedback!

 

[Randy Holmes-Farley Verified Community Expert]

Just to emphasize the concern about calibration, unless you are overdosing limewater or sodium carbonate, the results aren't accurate. No reef aquarium gets to pH 8.75 without a lot of high pH additions.

 

[acesfull44]

Just to emphasize the concern about calibration, unless you are overdosing limewater or sodium carbonate, the results aren't accurate. No reef aquarium gets to pH 8.75 without a lot of high pH additions.

Thank you for the feedback. I am not even dosing, so that can't be the issue. I will do a manual test today or tomorrow. I am also going to dip the probe as @reefjunkie suggested and re calibrate. Thanks again for the feedback!

 

[acesfull44]

Just to emphasize the concern about calibration, unless you are overdosing limewater or sodium carbonate, the results aren't accurate. No reef aquarium gets to pH 8.75 without a lot of high pH additions.

Thanks for the feedback, and the article you wrote was awesome!

 

[wpeterson]

I'll defer to more knowledgeable folks opinions above about pH probe reading too high.

However, if you have a large amount of macroalgae like chaetomorpha that are brightly lit over a long photo period and a tank with a lot of photosynthetic life in it, you can definitely raise the pH over time by absorbing too much of the CO2 out of the water faster than it can equalize with the air, which will raise your pH over time.

I've seen this cause a pH rise of 0.10-0.20 (ie: to 8.55 vs. 8.35 or so) when I had about two cubic feet of chaetomorpha in our refugium that was brightly lit. I had to reduce the photoperiod on the refugium until I culled about 2/3 of the chaetomorpha and things were back to normal.

That shouldn't be enough to get you to 8.75, though - so perhaps folks are right that your readings aren't accurate or something else is going on.