Climbing ph

[ask499]

Hey all,

I been battling an ongoing problem in 92 gallon where my ph keeps on climbing up to 8.5 and sometimes more. At 345 this morning I dosed 80ml of distilled vinegar and it dropped from 8.5 to 8.32. As of right now, it is already back up to 8.41 and climbing. I turned off my all dosing and my lights are off. Can anyone assist in what can cause it to continuously climb?

Thank you

 

[kharmaguru]

If you are not dosing kalkwasser or soda ash and your salinity is correct, then it's likely a testing or calibration error. 8.7 and under is fine btw, and most people would be envious of those numbers.

 

[kharmaguru]

Also, what is your alkalinity at?

 

[ask499]

Also, what is your alkalinity at?

These are my current values.

Please see attached

 

[kharmaguru]

These are my current values.

Please see attached

It all looks fine to me - even when your ph was 8.5. Do you have any manual test kits (Salifert, etc.) to verify numbers from the triton and ph probe? Do you check salinity with a refractometer occasionally?

 

[ask499]

It all looks fine to me - even when your ph was 8.5. Do you have any manual test kits (Salifert, etc.) to verify numbers from the triton and ph probe? Do you check salinity with a refractometer occasionally?

I haven’t tested manually in a long time. The apex system spoils you, but I do calibrate about every three to four months. At what range should I start worrying about the ph? From doing some digging I see some people panic with a ph of 8.5. Below, I have attached another picture showing the increase from the earlier screenshot to now.

 

[kharmaguru]

I haven’t tested manually in a long time. The apex system spoils you, but I do calibrate about every three to four months. At what range should I start worrying about the ph? From doing some digging I see some people panic with a ph of 8.5. Below, I have attached another picture showing the increase from the earlier screenshot to now.

Randy Holmes-Farley says 8.7 so that's what I go with.

 

[kharmaguru]

So out of curiousity do you run a skimmer and have good surface motion? If your PH is legitimately high then the usual reason is low CO2 in your water ( more likely if you are a kalk user). While most of us get higher PH by having those things, the truth is we are achieving a balance with the CO2 in the tank's environment (or outside air if we run a skimmer line). Anyway that same process will bring PH down if you have low CO2 in your system by bringing the tank into equilibrium with the CO2 in the air.

 

[ask499]

So out of curiousity do you run a skimmer and have good surface motion? If your PH is legitimately high then the usual reason is low CO2 in your water ( more likely if you are a kalk user). While most of us get higher PH by having those things, the truth is we are achieving a balance with the CO2 in the tank's environment (or outside air if we run a skimmer line). Anyway that same process will bring PH down if you have low CO2 in your system by bringing the tank into equilibrium with the CO2 in the air.

It's like you're reading my mind. So I do have my return from the sump pushing the surface of my water. I made this change about two weeks back. I decided to look back at the previous months before I made the change and my PH wasn’t climbing that high at all.

I did do a deep dive on CO2 levels last night to learn exactly what you stated above, but did not think of surface motion at all. Thanks for pointing that out to me. I am running a skimmer too but I’m not a kalk user.

So you're saying to run an outside air line for my skimmer to help bring down the PH? OR I can reduce my surface motion?

See attached images of water surface motion and skimmer used (would I connect the air line to the circle red spot?)

You been great help so far

Thank you

 

[kharmaguru]

So you're saying to run an outside air line for my skimmer to help bring down the PH? OR I can reduce my surface motion?

The opposite. If you truly have low CO2 in your system then adding surface motion will bring it up and thus the PH down. Outside air without a doubt has less CO2 than the air in your house so an outside airline would not be necessary.

There is a relationship between alkalinity, CO2 and PH. If you know two of the values you can calculate the other one. I believe you have some sort of testing error because you would need near 14dkh alkalinity at normal atmospheric CO2 levels (not likely inside a house) to have 8.5 PH. So either your PH measurement is wrong or it's right because your alk is actually off the scale.

Maybe you could sum up what you actually dose to this system, what filtration you're using and what lives in your tank so we have a better picture.

Here's a possibly helpful article though old and focused on low PH problems, the principles are still the same.

https://www.reefkeeping.com/issues/2004-09/rhf/index.htm

 

[griss]

I agree with Sean, something seems off in this scenario and I agree there might be testing error.

 

[ask499]

The opposite. If you truly have low CO2 in your system then adding surface motion will bring it up and thus the PH down. Outside air without a doubt has less CO2 than the air in your house so an outside airline would not be necessary.

There is a relationship between alkalinity, CO2 and PH. If you know two of the values you can calculate the other one. I believe you have some sort of testing error because you would need near 14dkh alkalinity at normal atmospheric CO2 levels (not likely inside a house) to have 8.5 PH. So either your PH measurement is wrong or it's right because your alk is actually off the scale.

Maybe you could sum up what you actually dose to this system, what filtration you're using and what lives in your tank so we have a better picture.

Here's a possibly helpful article though old and focused on low PH problems, the principles are still the same.

https://www.reefkeeping.com/issues/2004-09/rhf/index.htm

So, I change the surface water flow to not turn over so much and my ph have stopped rising so quickly. It has been staying steady around 8.45 and 8.50. I recalibrated the trident and ALK is spot on correct. I also calibrated my ph probe which is correct. please see below images for calibration test. The dip you see in ph is because of the calibration solution.

I only dose the Red Sea ALK and I have been dosing phosphate rx to battle some high phosphate levels. As far as filtration all I use just a protein skimmer and filter bag off my drain line.

 

[kharmaguru]

Between your two screens your alk went from 9.24 to 8.42, calcium from 594 to 445, and magnesium from 1310 to 1295. Either the Triton is dodgy or you had a precipitation event. The latter is actually more likely to happen with high PH.

Anyway, your issue is weird. Next test is turn off your skimmer for several hours and observe the ph result. If it still drops the reading value has to be an error or your tank is in an oxygen tent and you failed to mention it.

 

[kharmaguru]

Another RHf article that also specifically addresses high PH:

pH and the Reef Aquarium - REEFEDITION

A quote that illustrates where I've been going with all this:

"The most benign way to reduce high pH is to aerate the water more. Whether the aquarium looks well-aerated or not, and regardless of its oxygen level, if its pH is above 8.5 and its alkalinity is below 11 dKH (4 meq/L), then the aquarium is not fully equilibrated with carbon dioxide in the air (if its alkalinity is much higher than 11 dKH, then that may also require correction). Equilibrating carbon dioxide can be much more difficult than equilibrating oxygen. Air contains very little carbon dioxide (about 350 ppm) relative to oxygen (210,000 ppm). Consequently, a lot more air needs to be driven through the water to introduce the same amount of carbon dioxide as oxygen. Perfect aeration will solve nearly any high pH problem, and will rarely cause any problem of its own."

 

[ask499]

Another RHf article that also specifically addresses high PH:

pH and the Reef Aquarium - REEFEDITION

A quote that illustrates where I've been going with all this:

"The most benign way to reduce high pH is to aerate the water more. Whether the aquarium looks well-aerated or not, and regardless of its oxygen level, if its pH is above 8.5 and its alkalinity is below 11 dKH (4 meq/L), then the aquarium is not fully equilibrated with carbon dioxide in the air (if its alkalinity is much higher than 11 dKH, then that may also require correction). Equilibrating carbon dioxide can be much more difficult than equilibrating oxygen. Air contains very little carbon dioxide (about 350 ppm) relative to oxygen (210,000 ppm). Consequently, a lot more air needs to be driven through the water to introduce the same amount of carbon dioxide as oxygen. Perfect aeration will solve nearly any high pH problem, and will rarely cause any problem of its own."

Thanks!!! I will be doing some digging this weekend when I get back from vacation and let you know what's going on.

Thank you