PH 8.6 consistently without dosing

Mike Carroll · Mar 14, 2018

Hello,

This is my first post here, although I've been lurking for a while.

Background:
I have a 60 gal tank and around 15 gal in my sump.
I have a GFO/Carbon reactor and a skimmer with a gallon of bio balls in the sump.

For the first 3 months PH was at 8.3 other numbers have been great.. 0 amonia, 0 nitrite, 0 nitrate and 0 phosphate.

I added a single wall coral and anemone (BTA) and I also have 4 small fish, a shrimp, emerald crab and some snails..

I have not dosed at all, but did feed the Wall coral some Reef Chili just before this started, but I'm not sure it's related to the issue below..

Issue:
A few weeks ago, my wall coral stopped opening up like it had been and now appears to be bleaching slightly and the anemone didn't seem quite as happy barfing up some brown gunk after feeding..

The only thing I see wrong is the PH has climbed to 8.6, other numbers are consistent zeros..

I make RODI water and noticed my freshwater tank and ATO reservoir are also 8.6 so I think it may be coming in to the house like this from the city..

Should I start dosing vinegar to bring it down? Others say not to chase PH which I feel I would have to do.. So I'm looking for some advice from this amazing community!

I turned the lights on Full for the photo in case you might see something..

Crabs McJones · Mar 14, 2018

Mike Carroll said:
Hello,

This is my first post here, although I've been lurking for a while.

Background:
I have a 60 gal tank and around 15 gal in my sump.
I have a GFO/Carbon reactor and a skimmer with a gallon of bio balls in the sump.

For the first 3 months PH was at 8.3 other numbers have been great.. 0 amonia, 0 nitrite, 0 nitrate and 0 phosphate.

I added a single wall coral and anemone (BTA) and I also have 4 small fish, a shrimp, emerald crab and some snails..

I have not dosed at all, but did feed the Wall coral some Reef Chili just before this started, but I'm not sure it's related to the issue below..

Issue:
A few weeks ago, my wall coral stopped opening up like it had been and now appears to be bleaching slightly and the anemone didn't seem quite as happy barfing up some brown gunk after feeding..

The only thing I see wrong is the PH has climbed to 8.6, other numbers are consistent zeros..

I make RODI water and noticed my freshwater tank and ATO reservoir are also 8.6 so I think it may be coming in to the house like this from the city..

Should I start dosing vinegar to bring it down? Others say not to chase PH which I feel I would have to do.. So I'm looking for some advice from this amazing community!

I turned the lights on Full for the photo in case you might see something..

Welcome to R2R!!

welcome12_af875eaa887ed91c39e4c81c7d4fd966-0ed06ab93ea565647147c6beddbca4eb.gif

The PH of RO/DI water should be neutral at 7PH so if you're getting high ph out of your RO/DI one of your filters may not be functioning properly. Do you know what the TDS of your product water is?
#WelcometoR2R #reefsquad

Mike Carroll · Mar 14, 2018

crabs_mcjones said:
Welcome to R2R!!

The PH of RO/DI water should be neutral at 7PH so if you're getting high ph out of your RO/DI one of your filters may not be functioning properly. Do you know what the TDS of your product water is?
#WelcometoR2R #reefsquad

Thank you for the quick reply! I checked the PH of my tap water and it's 8.6.. I didn't trust my meter and had my local store test and they also saw it at 8.6.. :-/

Brew12 · Mar 14, 2018

Mike Carroll said:
Hello,

This is my first post here, although I've been lurking for a while.

Background:
I have a 60 gal tank and around 15 gal in my sump.
I have a GFO/Carbon reactor and a skimmer with a gallon of bio balls in the sump.

For the first 3 months PH was at 8.3 other numbers have been great.. 0 amonia, 0 nitrite, 0 nitrate and 0 phosphate.

I added a single wall coral and anemone (BTA) and I also have 4 small fish, a shrimp, emerald crab and some snails..

I have not dosed at all, but did feed the Wall coral some Reef Chili just before this started, but I'm not sure it's related to the issue below..

Issue:
A few weeks ago, my wall coral stopped opening up like it had been and now appears to be bleaching slightly and the anemone didn't seem quite as happy barfing up some brown gunk after feeding..

The only thing I see wrong is the PH has climbed to 8.6, other numbers are consistent zeros..

I make RODI water and noticed my freshwater tank and ATO reservoir are also 8.6 so I think it may be coming in to the house like this from the city..

Should I start dosing vinegar to bring it down? Others say not to chase PH which I feel I would have to do.. So I'm looking for some advice from this amazing community!

I turned the lights on Full for the photo in case you might see something..

Welcome to Reef2Reef!

pH in a reef tank is a function of Alkalinity and CO2 content. What is your Alkalinity at?

I suspect you aren't getting a good pH reading. How are you measuring it?

If I had to take a guess, I would say that your phosphate is too low. I would stop running GFO and see if that improves things.

Mike Carroll · Mar 14, 2018

Brew12 said:
Welcome to Reef2Reef!

pH in a reef tank is a function of Alkalinity and CO2 content. What is your Alkalinity at?

I suspect you aren't getting a good pH reading. How are you measuring it?

If I had to take a guess, I would say that your phosphate is too low. I would stop running GFO and see if that improves things.

I don't have a test for Alkalinity.. I did shut off the GFO to see if that changes things.. I'm using a Dr Meter PH tester I bought off Amazon.. Like I mentioned earlier, I didn't trust it, but local fish store got the same reading.. and I also get it from my API Marine saltwater test kit.. and I'm getting this reading from my tap water.. My freshwater tank was always 8.3 using straight tap water, but it has also gone up...

Brew12 · Mar 14, 2018

Mike Carroll said:
I don't have a test for Alkalinity.. I did shut off the GFO to see if that changes things.. I'm using a Dr Meter PH tester I bought off Amazon.. Like I mentioned earlier, I didn't trust it, but local fish store got the same reading.. and I also get it from my API Marine saltwater test kit.. and I'm getting this reading from my tap water.. My freshwater tank was always 8.3 using straight tap water, but it has also gone up...

I wouldn't trust readings on RODI too much. There aren't enough ions in the water to get a stable, accurate reading.

What is your salinity?

Even if your tap water was high, it wouldn't impact your reef tank. pH in a reef tank is only impacted by Alkalinity and CO2 content. If your pH is actually that high you either have a dangerously high Alkalinity or a low amount of CO2. If the issue is low CO2, consider yourself lucky and enjoy the high pH. Odds are it won't stay high long. If it is high Alkalinity, do a large water change to drop it.

Shutting off the GFO should help, and feed the tank heavy to get some more nutrients in it. The reef chili is a great product to use to do that. LPS and Softies like having nutrients in the water. Even SPS's need some nutrients. I lost my first few corals, including a hammer coral, because I was running GFO in my system and I shouldn't have been.

Mike Carroll · Mar 14, 2018

Brew12 said:
What is your salinity?

Salinity 1.024 before water change 1.023 after..

Thank you very much for the educated reply! I really appreciate it!

I did find I had some test strips which show Alkalinity.. it's reading about 120 (mg/l) I have no idea if this is high, low or just right..

Maybe it's the lack of Phosphate.. To complicate things.. I just did a 40% water change earlier today trying to "fix" the PH.. so the Alk reading could also be flawed from that..

Lovemyreef2015 · Mar 14, 2018

Welcome to R2R

chipmunkofdoom2 · Mar 14, 2018

Do you have a link to the pH meter you bought? When I search for that name, several models come up.

If the meter cost less than $20, I would say this is testing error. A quality pH probe and meter will cost you around $100. 8.6 is pretty close to what we normally measure in reefs, but "pretty close" might be the best a <$20 meter can do in seawater. Have you tried calibrating the meter? Can it be calibrated?

Jason mack · Mar 14, 2018

Welcome to R2R!!

DSC reef · Mar 14, 2018

Welcome to R2R

Mike Carroll · Mar 14, 2018

chipmunkofdoom2 said:
Do you have a link to the pH meter you bought? When I search for that name, several models come up.

If the meter cost less than $20, I would say this is testing error. A quality pH probe and meter will cost you around $100. 8.6 is pretty close to what we normally measure in reefs, but "pretty close" might be the best a <$20 meter can do in seawater. Have you tried calibrating the meter? Can it be calibrated?

Link to Meter

It was definitely cheap, never calibrated, but is consistent with my API test kit and local fish store..

Robink · Mar 14, 2018

You need to get a reef test kit, should have calcium, alk and magnesium. Corals need stability especially in alk. I use the red sea reef foundation pro test kit. you can get it on amazon. Fwiw I test my alk everyday.
Welcome to R2R and the hobby!

Brew12 · Mar 14, 2018

Mike Carroll said:
Salinity 1.024 before water change 1.023 after..

Thank you very much for the educated reply! I really appreciate it!

I did find I had some test strips which show Alkalinity.. it's reading about 120 (mg/l) I have no idea if this is high, low or just right..

Maybe it's the lack of Phosphate.. To complicate things.. I just did a 40% water change earlier today trying to "fix" the PH.. so the Alk reading could also be flawed from that..

120mg/l is 6.7dkh so it is a little low, which isn't a problem for you right now. Odds are it is a little higher than that, but test strips aren't very accurate. It isn't likely contributing to your high pH.

So we are back to low CO2 which isn't much of a problem or a bad reading. Either way, I wouldn't worry about your pH any more.

A water change is almost always a good thing, it is hard to do damage by doing one if you do it correctly. No harm done there.

I would let your NO3/PO4 rise and hopefully your system will recover.

Lasse · Mar 14, 2018

Welcome to R2R

I think it is very important to know how these types of pH meters work and how these meters can give us a measurement of the parameter we call pH. They in reality measure the potential differens between the positive hydronium (H3O+) and the negative hydroxide ion (OH-) When I was in school, many years ago, we learned free hydrogen ions (H+) and free hydrogen ions (OH-) but it have changes nowadays to H3O+ and OH- but they have not change pH to pH3O that have been more right today. We still talk about pH. If this potential differens is 0 mV - it means that is as many positive H3O ions as negative HO ions - the pH is 7. If there is more negative ions (more HO ions) -> pH>7 and if it more positive ions (H3O ions) -> pH < 7. The electrodes is constructed in that way that they are linear to the potential difference in nearly the whole pH scale (0-14). A change of 1 pH unit will result in a change of the same mV in the whole range. In modern pH electrodes this "slope" is between 56 and 59 mV for each pH unit. If we calculate with a probe with the "slope" of 56 mV - it means that 0 mV is pH 7; + 56 mV is pH 6 and -56 mV is pH 8; +112 mV = pH 5 and - 112 mV = pH9; +168 mV : pH4 and -168 is pH 10.

The probe will measure a mV signal - this signal will be transformed to a pH value that we can read but there is not anything like perfect probes and the probes will change their slope by age. Therefor we have the calibration process. We use a calibration solution with known pH of 7. Whatever our probe read in mV - we say to the meter - this 0 mV - pH 7. But we do not know the real slope of the probe - we have to calculate that too. For us - working with pH over 7 - we take a solution with known pH of 9 (or 10) . Let the probe stabilize and say to the meter - this is pH 9 (or 10) and it will calculate the right slope for us. Now the meter can report the right pH for us in the mV range of 0 to around -112 mV. When I first started with pH meters there still was meters that did not do this conversions of themselves - we had to read mv signals and do a calibration curve that we could use to determine the pH of a water sample but there was also meters that did it by themselves.

What I want to say - these meters is useless without calibration and you NEED to do a 2 point calibration. These cheap meters sometimes do not allow a two point calibration.

Sincerely Lasse

Mike Carroll · Mar 14, 2018

Lasse said:
Welcome to R2R

I think it is very important to know how these types of pH meters work and how these meters can give us a measurement of the parameter we call pH. They in reality measure the potential differens between the positive hydronium (H3O+) and the negative hydroxide ion (OH-) When I was in school, many years ago, we learned free hydrogen ions (H+) and free hydrogen ions (OH-) but it have changes nowadays to H3O+ and OH- but they have not change pH to pH3O that have been more right today. We still talk about pH. If this potential differens is 0 mV - it means that is as many positive H3O ions as negative HO ions - the pH is 7. If there is more negative ions (more HO ions) -> pH>7 and if it more positive ions (H3O ions) -> pH < 7. The electrodes is constructed in that way that they are linear to the potential difference in nearly the whole pH scale (0-14). A change of 1 pH unit will result in a change of the same mV in the whole range. In modern pH electrodes this "slope" is between 56 and 59 mV for each pH unit. If we calculate with a probe with the "slope" of 56 mV - it means that 0 mV is pH 7; + 56 mV is pH 6 and -56 mV is pH 8; +112 mV = pH 5 and - 112 mV = pH9; +168 mV : pH4 and -168 is pH 10.

The probe will measure a mV signal - this signal will be transformed to a pH value that we can read but there is not anything like perfect probes and the probes will change their slope by age. Therefor we have the calibration process. We use a calibration solution with known pH of 7. Whatever our probe read in mV - we say to the meter - this 0 mV - pH 7. But we do not know the real slope of the probe - we have to calculate that too. For us - working with pH over 7 - we take a solution with known pH of 9 (or 10) . Let the probe stabilize and say to the meter - this is pH 9 (or 10) and it will calculate the right slope for us. Now the meter can report the right pH for us in the mV range of 0 to around -112 mV. When I first started with pH meters there still was meters that did not do this conversions of themselves - we had to read mv signals and do a calibration curve that we could use to determine the pH of a water sample but there was also meters that did it by themselves.

What I want to say - these meters is useless without calibration and you NEED to do a 2 point calibration. These cheap meters sometimes do not allow a two point calibration.

Sincerely Lasse

Thank you Lasse for this very detailed response! and thank you for the summary, I doubt I would have "gotten" it without it..

I'll invest in a better meter.. and I'll make sure it can do a two part calibration to account for the slope.. Great advice!!

Mike Carroll · Mar 14, 2018

Brew12 said:
120mg/l is 6.7dkh so it is a little low, which isn't a problem for you right now. Odds are it is a little higher than that, but test strips aren't very accurate. It isn't likely contributing to your high pH.

So we are back to low CO2 which isn't much of a problem or a bad reading. Either way, I wouldn't worry about your pH any more.

A water change is almost always a good thing, it is hard to do damage by doing one if you do it correctly. No harm done there.

I would let your NO3/PO4 rise and hopefully your system will recover.

Thanks Brew12!! I'll follow your advice!

I appreciate all of the kind responses I've received for my silly little problems.. and I feel welcome in the community.. Fantastic job everyone!!

Brew12 · Mar 14, 2018

Mike Carroll said:
Thank you Lasse for this very detailed response! and thank you for the summary, I doubt I would have "gotten" it without it..

I'll invest in a better meter.. and I'll make sure it can do a two part calibration to account for the slope.. Great advice!!

One last piece of advice? Don't bother with a better pH meter yet. Make sure you can test for Alk, Calc, NO3, Mg and PO4 to start. If your alk is in line, the pH should follow.