Is it my PH probe or something else?

[ChrisQ0904]

I have recently been going crazy trying to figure out why my PH is constantly reading low (7.5-7.8) I have a chaeto reactor and run the light at night and still have no luck. I have tried a C02 Scrubber and that gets depleted in less than 24hrs so that is not a cost effective option. I have checked with other test kits and get a ph reading of 7.8 and as of now my corals seem to be doing pretty good. Due to my corals doing good I got to wondering maybe my probe is bad and its time to buy a new one? The problem is I don't remember how old my probe is and the reading doesn't change even after I calibrate the probe.

 

[Randy Holmes-Farley Verified Community Expert]

I expect the pH is actually low. Low pH will mostly be an issue for hard corals, not soft ones since it is the deposition (or dissolution) of calcium carbonate skeletons that is the issue.

If things seem OK, don't agonize over it, but the source is almost certainly elevated CO2 in your home air (especially if the media depletes that fast).

It may be high enough to be unhealthy for you.

 

[Brew12]

I have recently been going crazy trying to figure out why my PH is constantly reading low (7.5-7.8) I have a chaeto reactor and run the light at night and still have no luck. I have tried a C02 Scrubber and that gets depleted in less than 24hrs so that is not a cost effective option. I have checked with other test kits and get a ph reading of 7.8 and as of now my corals seem to be doing pretty good. Due to my corals doing good I got to wondering maybe my probe is bad and its time to buy a new one? The problem is I don't remember how old my probe is and the reading doesn't change even after I calibrate the probe.

While your probe could be bad, if you are depleting your CO2 scrubber media in a day you have something else going on. I would check your home CO2 levels as they could be dangerous.

 

[ChrisQ0904]

Ok, now you guys are freaking me out. How the hell do I test the c02 levels in my house?

 

[jsker]

It not only you, I am having the same experience. I have had a line from my skimmer to the outside fresh air and my ph is still low. I read that you had a scrubber, I am adding a scrubber to the outside air line to see if that helps. Here is a write up by @Randy Holmes-Farley link . I would say it is more that the house is closed up and not the probe. I thought it was the probe and I just replaced the probe, calibrated the probe and the readings are the same. The only change I have made is a new A/C system and they did such a good job sealing things up that my co2 is higher in the house now.

 

[Brew12]

Ok, now you guys are freaking me out. How the hell do I test the c02 levels in my house?

It is possible that your local fire department can come test it for you. HVAC installers should be able to test it also. If you would rather do it yourself and don't mind it not being incredibly accurate, you can get something like this.
https://www.amazon.com/Active-Air-COTEST-CO2-Tester/dp/B009G6108U

 

[jsker]

Ok, now you guys are freaking me out. How the hell do I test the c02 levels in my house?

I guess you could try one of these link . The electronic one are pricy.

 

[Brew12]

I guess you could try one of these link . The electronic one are pricy.

That is carbon monoxide, not carbon dioxide.

 

[Tariq]

To quickly verify if your house CO2 is higher than outside.
Fill up a bowl of water from your tank, note the pH.
Take the bowl outside and put an air tubing connected to an air-pump and aerate the water using fresh outside air for about 20 min.
Measure the pH of this water to see a difference.

 

[jsker]

It is possible that your local fire department can come test it for you. HVAC installers should be able to test it also. If you would rather do it yourself and don't mind it not being incredibly accurate, you can get something like this.
https://www.amazon.com/Active-Air-COTEST-CO2-Tester/dp/B009G6108U

Great recommendation

 

[ChrisQ0904]

I expect the pH is actually low. Low pH will mostly be an issue for hard corals, not soft ones since it is the deposition (or dissolution) of calcium carbonate skeletons that is the issue.

If things seem OK, don't agonize over it, but the source is almost certainly elevated CO2 in your home air (especially if the media depletes that fast).

It may be high enough to be unhealthy for you.

The tank is nothing but sps and they all seem to be growing just fine which is what was driving me crazy. I trying to not overthink it but ironically I have been seeing a bunch of things recently that promote higher ph = healthier corals which is why im starting to freak out again.

 

[ChrisQ0904]

To quickly verify if your house CO2 is higher than outside.
Fill up a bowl of water from your tank, note the pH.
Take the bowl outside and put an air tubing connected to an air-pump and aerate the water using fresh outside air for about 20 min.
Measure the pH of this water to see a difference.

Guess im off to go buy an airstone.

 

[ChrisQ0904]

well just some food for thought... I added some tubing to my skimmer to my window and within 30min I went from 7.5 to 7.6, so that seems to help a little bit. I am going to try and keep it there most of the day(well the rest of it) and see how high it will go. IF it increases to 8+ I will want to run this as a more permanent setup but the window is on the ground floor and I live in Florida so leaving the window open 24/7 is not really an option.

 

[XNavyDiver]

I'll jump in and mirror many here, I am having the same issue. I added a scrubber a couple of days ago. I hooked it up to my skimmer around 4 in the afternoon and by the early morning my pH shot up to 8.5! I unhooked it and let it come down and then hooked it back up. It has seemed to level out now at about 8.35 or so. I'm encouraged right now as its been pretty stable for a day now at 8.3-8.35. My tank is also sps dominant and they are all liking it better (at least visually) at this pH than they were at 7.8-7.9 that my tank runs at without the scrubber. Crossing my fingers for continued stability!

 

[jsker]

I'll jump in and mirror many here, I am having the same issue. I added a scrubber a couple of days ago. I hooked it up to my skimmer around 4 in the afternoon and by the early morning my pH shot up to 8.5! I unhooked it and let it come down and then hooked it back up. It has seemed to level out now at about 8.35 or so. I'm encouraged right now as its been pretty stable for a day now at 8.3-8.35. My tank is also sps dominant and they are all liking it better (at least visually) at this pH than they were at 7.8-7.9 that my tank runs at without the scrubber. Crossing my fingers for continued stability!

That is great to hear. Tomorrow I pick up my soda lime, and I will go on line with the scrubber.

 

[Randy Holmes-Farley Verified Community Expert]

Ok, now you guys are freaking me out. How the hell do I test the c02 levels in my house?

A CO2 meter, and they aren't cheap.

However, at an alkalinity of about 7 dKH, normal outside air will equilibrate with the tank water to give a pH of about 8.1-8.2.

Each doubling of the CO2 level lowers it by about 0.3 pH units.

To get to pH 7.6, the CO2 level will be about 4x normal air. That puts it over 1000 ppm.

1000 ppm is generally considered the acceptable limit before you should do something.

 

[jsker]

A CO2 meter, and they aren't cheap.

However, at an alkalinity of about 7 dKH, normal outside air will equilibrate with the tank water to give a pH of about 8.1-8.2.

Each doubling of the CO2 level lowers it by about 0.3 pH units.

To get to pH 7.6, the CO2 level will be about 4x normal air. That puts it over 1000 ppm.

1000 ppm is generally considered the acceptable limit before you should do something.

Good to know, and thank you Randy

 

[ChrisQ0904]

A CO2 meter, and they aren't cheap.

However, at an alkalinity of about 7 dKH, normal outside air will equilibrate with the tank water to give a pH of about 8.1-8.2.

Each doubling of the CO2 level lowers it by about 0.3 pH units.

To get to pH 7.6, the CO2 level will be about 4x normal air. That puts it over 1000 ppm.

1000 ppm is generally considered the acceptable limit before you should do something.

So nothing to freak out about too much just yet? I'm just flirting between bad and ok.

 

[Reefltx]

Have you checked the date on your probe?
If it's an apex probe, the date is on the wire. I just replaced my old probe with a new lab grade apex ph probe. After calibration I'm getting .2 higher than my old probe.

 

[ChrisQ0904]

Have you checked the date on your probe?
If it's an apex probe, the date is on the wire. I just replaced my old probe with a new lab grade apex ph probe. After calibration I'm getting .2 higher than my old probe.

WOW, so let me tell you how dumb I feel right now.... date is September 15