Relationship between Temp and ph (1 Viewer)

[RocketSurgeon]

I've noticed that when my temperature rises, typically my ph rises as well.

Is this normal behavior?

My sump light turns on in the evening and shuts off in the morning.

 

[rxonco]

I think it's more likely that you're getting the slight daytime increase that is to be expected.

 

[RocketSurgeon]

I think it's more likely that you're getting the slight daytime increase that is to be expected.

I expect that, but this morning when the temp dropped lower, so did my ph.
Tank temp dropped due to ceiling fan being turned on.

The additional air flow lowered the ph?

 

[rxonco]

More air flow = less CO2? I'm no expert in this area. I don't even test my pH.

 

[soymilk]

i think its prob due to the levels of CO2 in the house. Im not sure when you have your tank lights on, but in my house, the highest point in temp is prob around noon.

Around noon no one is at my house, so I would expect this time to be when the pH level would be highest because the ambient co2 levels in the house is low.

 

[RocketSurgeon]

More air flow = less CO2? I'm no expert in this area. I don't even test my pH.

And I normally don't pay any attention to mine. Since I was gone for 4 days without anyone touching the tank, I was watching my controller numbers a lot closer.

 

[RocketSurgeon]

i think its prob due to the levels of CO2 in the house. Im not sure when you have your tank lights on, but in my house, the highest point in temp is prob around noon.

Around noon no one is at my house, so I would expect this time to be when the pH level would be highest because the ambient co2 levels in the house is low.

Somehow I knew this wasn't going to be a simple answer...

For 4 days, no one was in the house, so the variables were limited. Now that everyone is at home again, I'm not sure I could repeat the same test.

My lighting schedule:

If Time > 11:00 Then BLU ON
If Time > 22:15 Then BLU OFF

If Time > 12:30 Then WHT ON
If Time > 21:15 Then WHT OFF

If Time > 17:35 Then FUG ON
If Time > 08:05 Then FUG OFF

I guess it's not a big deal. Just when I quickly googled for an answer, it appeared the ph should drop with a rise in temp. Made me curious, as that was not the experience I received.

 

[soymilk]

I fall at reading, didnt notice you had the times on the spreadsheet earlier until I looked at it again.

From what I understand, as water temp goes up. It gets harder for the water to hold oxygen. So ph falls a little.

But I think this has more to do with the cellular respriration we were talking about in a DIY thread earlier this year.

I don't think it has to do with your temp. Does the older acIII have a chart?

If it does have to do with temp, then you would k

 

[soymilk]

I fall at reading, didnt notice you had the times on the spreadsheet earlier until I looked at it again.

From what I understand, as water temp goes up. It gets harder for the water to hold oxygen. So ph falls a little.

But I think this has more to do with the cellular respriration we were talking about in a DIY thread earlier this year. I don't think it has to do with your temp. Does the older acIII have a chart?

If it does have to do with temp, then you would notice a steady climb as the temp rises. If it's just a sudden increase. It's more likely the normal stuff that causes pH to fluctuate.

 

[RocketSurgeon]

Extremely consistent over the past several days, that when temp rose, so did ph., and when temp fell, so did the ph.

 

[TexanReef]

Your consistent correlation between temperature and pH is spooky considering conventional wisdom seems to point to an inverse relationship.

Dumb question but is the pH probe temperature compensated by whatever software is reporting the results? I know the pH probe I use when brewing requires a correction (which the unit kindly does for me.) Brewing and math do not mix, by the way.

 

[Txstateunivreefer]

ph is influenced by dissolved CO2 the more CO2 the more dissolved carbonic acid your water will contain. So increased CO2 will cause your pH to drop like a rock.

Now the relationship to temperature. Levels of dissolved gasses and temperature have an inverse relationship as temp decreases, concentration of dissolved gasses increases. for example an ice cold soda fizzes less because it can contain more CO2 in solution.


With both of those combined as temp goes up CO2 is released lowering the levels of carbonic acid making the ph rise.

so yes its normal. you would see a larger change at night as your temp decreases from lights turning off but i am assuming that you have algae in your fuge that helps by consuming some of the CO2 that would cause your pH to drop more at night than you are seeing.

 

[Reefnewbie]

Not going into major detail, but I work in a lab. The ph meter has a thermal probe built in. The ph standards we have all list their levels @25c. Yes, temp does have an affect on ph.