Ph and Air

[Reefer1978]

I have an odd situation in my QT. When I add prazi, I usually turn on the air stone to compensate for any potential low oxigen situation. But last time I did that, my Ph went drastically down, 7.5 territory overnight, which I could kinda understand for being in the basement, potentially high Co2 environment.

I just moved the airpump outdoors. Pump is outside, air hose and electrical cord are through the plastic window, gap is taped shut given it's winter time. I turned on the air about an hour ago, and Ph keeps going down. Any thoughts?

 

[Randy Holmes-Farley Verified Community Expert]

Prazipro has a substantial organic carbon component and its metabolism will tend to lower pH. The aeration itself is not driving that unless the CO2 level in the air is very high.

 

[Reefer1978]

Prazipro has a substantial organic carbon component and its metabolism will tend to lower pH. The aeration itself is not driving that unless the CO2 level in the air is very high.

I have not added Prazi yet. Co2 inside the basement it at 500. But, air source is outside. What that still drive Ph down from air exchange?

 

[Randy Holmes-Farley Verified Community Expert]

I have not added Prazi yet. Co2 inside the basement it at 500. But, air source is outside. What that still drive Ph down from air exchange?

Not that low. Maybe the pH is inaccurate.

 

[Reefer1978]

Not that low. Maybe the pH is inaccurate.

It's 7.72 right now.

 

[Randy Holmes-Farley Verified Community Expert]

It's 7.72 right now.

Try aerating a cup of water.

http://www.reefedition.com/ph-and-the-reef-aquarium/
The Aeration Test

Some of the possible causes of low pH listed above require an effort to diagnose. Problems 3 and 4 are quite common, and here is a way to distinguish them. Remove a cup of tank water and measure its pH. Then aerate it for an hour with an airstone using outside air. Its pH should rise if it is unusually low for the measured alkalinity (Figure 2). Then repeat the same experiment on a new cup of water using inside air. If its pH also rises, then the aquarium’s pH will rise simply with more aeration because it is only the aquarium that contains excess carbon dioxide. If the pH does not rise in the cup (or rises very little) when aerating with indoor air, then that air likely contains excess CO2, and more aeration with that same air will not solve the low pH problem (although aeration with fresher air should). Be careful implementing this test if the outside aeration test results in a large temperature change (more than 5°C or 10°F), because such changes alone impact pH measurements.

 

[Reefer1978]

Try aerating a cup of water.

http://www.reefedition.com/ph-and-the-reef-aquarium/
The Aeration Test

Some of the possible causes of low pH listed above require an effort to diagnose. Problems 3 and 4 are quite common, and here is a way to distinguish them. Remove a cup of tank water and measure its pH. Then aerate it for an hour with an airstone using outside air. Its pH should rise if it is unusually low for the measured alkalinity (Figure 2). Then repeat the same experiment on a new cup of water using inside air. If its pH also rises, then the aquarium’s pH will rise simply with more aeration because it is only the aquarium that contains excess carbon dioxide. If the pH does not rise in the cup (or rises very little) when aerating with indoor air, then that air likely contains excess CO2, and more aeration with that same air will not solve the low pH problem (although aeration with fresher air should). Be careful implementing this test if the outside aeration test results in a large temperature change (more than 5°C or 10°F), because such changes alone impact pH measurements.

@Randy Holmes-Farley I will do the test tomorrow when it's warm outside. But also wanted to give a small update, I put the air pump on full blast, and Ph started going up.