Ozone & pH

[cvicente]

I've been experiencing a steady rise in pH since I added an ozone generator to my system, to the point that my pH now ranges from 8.25 - 8.5 from the 8.05 - 8.25 I was measuring. The meter is calibrated with Hach 7 - 10 references. I've always used a calcium reactor to keep my alkalinity in the 11-12 dKH range due to my high nutrient levels. Although I don't use a dryer and some nitric acid could be forming it doesn't seem to have a noticeable impact on pH. Besides carbonic and nitric acid, what other acids or organics known to affect pH are being oxidized by ozone and could be causing this rise on pH? Excluding the ozone generator the setup has been the same for the past 6 months.

 

[Randy Holmes-Farley]

I'm not sure why you are seeing the effect you are. I didn't notice a pH rise when initiating ozone, and I cannot think of any reactions that would do so.

Where is the probe in relation to the ozone addition?

 

[cvicente]

The pH probe is located in the first chamber of the sump, the ozone is injected in one of the two pumps of the skimmer. The skimmer is located in the middle area of the sump. The probe and the skimmer have been in the same place since last year. The rise in pH has been steady for the past couple of months.

 

[Randy Holmes-Farley]

The pH probe is located in the first chamber of the sump, the ozone is injected in one of the two pumps of the skimmer. The skimmer is located in the middle area of the sump. The probe and the skimmer have been in the same place since last year. The rise in pH has been steady for the past couple of months.

Have you recently recalibrated it?

 

[Randy Holmes-Farley]

FWIW, I'm not sure if you've seen it, but I review the chemistry of ozone and its reactions in a reef tank here:

Ozone and the Reef Aquarium, Part 1: Chemistry and Biochemistry by Randy Holmes-Farley - Reefkeeping.com

Ozone and the Reef Aquarium, Part 2: Equipment and Safety by Randy Holmes-Farley - Reefkeeping.com

Ozone and the Reef Aquarium, Part 3: Changes in a Reef Aquarium upon Initiating Ozone by Randy Holmes-Farley - Reefkeeping.com

 

[cvicente]

Have you recently recalibrated it?

Yes, about three weeks ago

 

[Randy Holmes-Farley]

OK, well, I'm not sure why you are observing these pH changes. :)

 

[Chip]

OK, well, I'm not sure why you are observing these pH changes. :)

I'm very late to the game I know but anyone figure out this phenomenon?. I am also noticing a nice increase in higher ph. Running in a 600 gallon tank with a 180 gallon sump. Both probes are newer with a year and calibrated last week. Just recently started using the ozone again. I was using kalkwasser religiously for years. Found that I was precipitating out a lot of my elements. So I went back to a two part. FM balling light and now my pH is climbing higher at night when I run the ozone. I'm running 3 times a day for 1 hour at lights out. Very weird. Kind of freaking me out.

 

[Randy Holmes-Farley]

I'm very late to the game I know but anyone figure out this phenomenon?. I am also noticing a nice increase in higher ph. Running in a 600 gallon tank with a 180 gallon sump. Both probes are newer with a year and calibrated last week. Just recently started using the ozone again. I was using kalkwasser religiously for years. Found that I was precipitating out a lot of my elements. So I went back to a two part. FM balling light and now my pH is climbing higher at night when I run the ozone. I'm running 3 times a day for 1 hour at lights out. Very weird. Kind of freaking me out.

Have you recently recalibrated the probe?

I don’t think pH ever rises too high in a decently aerated reef tank that is not using high pH additives (you are not).