When should you care about pH?

FunkEngine · Nov 3, 2017

So I know that a lot of people fall into the trap of chasing pH numbers, but at what point does it become too low, and it becomes time to actually do something about it?

I know my tank has low pH, and frankly, I think its pretty low at that. During the day pH peaks at 7.8-7.9 and at night drops to almost 7.5, and all of this is with kalk in the top off water. I'm thinking that this is low enough that I probably should actually do something about it, is that the case?

Reef Able · Nov 3, 2017

When was the last time you calibrated your pH probe. 7.5 sounds to be too low but i doubt your pH is that low. I had this problem earlier this year when i moved my sump into basement. I was getting a constant reading around 7.65 however all my corals in my display were looking nice and healthy. I went ahead and got a portable pH probe and tested it on my sump and display. My sump pH showed 7.85 and in my display which is in the family room the floor above it showed 8.02...This pointed me towards the probe. When i took my pH probe out i saw there was a minor crack on it which explains why i was getting a constant low reading. I replaced with a new pH probe and now my reading is constant between 7.85 - 8...Don't chase pH until you see any difference in your corals...the last thing you want is create another issue trying to fix one which is so common in this hobby...

Evan West · Nov 3, 2017

FunkEngine said:
So I know that a lot of people fall into the trap of chasing pH numbers, but at what point does it become too low, and it becomes time to actually do something about it?

I know my tank has low pH, and frankly, I think its pretty low at that. During the day pH peaks at 7.8-7.9 and at night drops to almost 7.5, and all of this is with kalk in the top off water. I'm thinking that this is low enough that I probably should actually do something about it, is that the case?

Yes I would say that this is a case were you should care. really you dont want Ph below 7.8. I tend to side with not chasing numbers......unless those numbers are way off. There are a number of things you can do to help this tho. First increase aeration by making sure the surface of the water is breaking allowing gas exchange. Next you can open a window to get fresh air into the room, you can also use a C02 scrubber on you skimmer intake or run a line outside. In addition to this stuff, running a refugium on the reverse cycle of your tank lights will help even out swings and keep the PH higher overall. Kalkwasser also helps drive Ph up.

FunkEngine · Nov 3, 2017

Reef Able said:
When was the last time you calibrated your pH probe. 7.5 sounds to be too low but i doubt your pH is that low. I had this problem earlier this year when i moved my sump into basement. I was getting a constant reading around 7.65 however all my corals in my display were looking nice and healthy. I went ahead and got a portable pH probe and tested it on my sump and display. My sump pH showed 7.85 and in my display which is in the family room the floor above it showed 8.02...This pointed me towards the probe. When i took my pH probe out i saw there was a minor crack on it which explains why i was getting a constant low reading. I replaced with a new pH probe and now my reading is constant between 7.85 - 8...Don't chase pH until you see any difference in your corals...the last thing you want is create another issue trying to fix one which is so common in this hobby...

I calibrated it a little while ago, twice actually. I was getting 8-8.2 then performed routine calibration, which lowered it down to where it is now. I thought that was weird, so I calibrated again with the same results. This was a month or two ago, so I'll do it again to make sure it is reading accurately.

FunkEngine · Nov 3, 2017

Evan West said:
Yes I would say that this is a case were you should care. really you dont want Ph below 7.8. I tend to side with not chasing numbers......unless those numbers are way off. There are a number of things you can do to help this tho. First increase aeration by making sure the surface of the water is breaking allowing gas exchange. Next you can open a window to get fresh air into the room, you can also use a C02 scrubber on you skimmer intake or run a line outside. In addition to this stuff, running a refugium on the reverse cycle of your tank lights will help even out swings and keep the PH higher overall. Kalkwasser also helps drive Ph up.

Winter is coming where I live so opening a window is no longer an option. I was doing this previously, and it was able to elevate pH up about .2 points. I'm currently debating the merits between a refugium and a scrubber.

Ashish Patel · Nov 3, 2017

I don't test it.. I monitored it with the seneye by default for the first 1 month and got a good idea of where I stand. I have a refugium on reverse photoperiod, Alot of fresh air and it tested 8-8.3 all the time. I see alot of benefit in monitoring it but not so much testing it! This will help you catch an issue such as dosing pump, Kalk, and CA Reactor malfunction.

Ashish Patel · Nov 3, 2017

To answer the questions since I totally mis interpreted your posted

1. When you know your have no fresh air!.
2. when you know their will be swings.
3. when you run a calcium reactor.
4. When ALK swings so should PH> I believe lol

Brew12 · Nov 3, 2017

FunkEngine said:
I calibrated it a little while ago, twice actually. I was getting 8-8.2 then performed routine calibration, which lowered it down to where it is now. I thought that was weird, so I calibrated again with the same results. This was a month or two ago, so I'll do it again to make sure it is reading accurately.

Did you use new calibration fluids or the same fluids for both calibrations? I don't believe your results are accurate. How old is your pH probe?

Might be worth picking up a cheap API pH test kit just to have a way to verify your numbers.

FunkEngine · Nov 3, 2017

Brew12 said:
Did you use new calibration fluids or the same fluids for both calibrations? I don't believe your results are accurate. How old is your pH probe?

Might be worth picking up a cheap API pH test kit just to have a way to verify your numbers.

Its the probe included with the 2016 Apex, its less than 1 year old. New packets were used for each calibration. I even rinsed the probe with DI water and patted the probe dry between fluids to reduce contamination as much as I could.

Brew12 · Nov 3, 2017

FunkEngine said:
Its the probe included with the 2016 Apex, its less than 1 year old. New packets were used for each calibration. I even rinsed the probe with DI water and patted the probe dry between fluids to reduce contamination as much as I could.

Doesn't sound like that could have caused an issue.

How high is your alk?

FunkEngine · Nov 3, 2017

Brew12 said:
Doesn't sound like that could have caused an issue.

How high is your alk?

8-9, depending on the month.

Brew12 · Nov 3, 2017

FunkEngine said:
8-9, depending on the month.

I used to have a chart showing CO2 concentrations as they relate to pH and Alk but I can't find it.

If I were you, I would run a quick and easy test. Get a sample of water from your aquarium and take it outside along with an air pump/air stone. Let it aerate for a few minutes then bring it in and put your pH probe in it. If it doesn't read at least 8.2 you know your probe isn't reading accurately.

If you don't have an air pump you can do almost the same thing using a larger container and a whisk. Just whisk it up good and fast to try and get lots of air exchange.

The only other thing that would make sense for your pH to be this low would be if you had a lot of bacteria in your system that were consuming oxygen and releasing CO2. I am assuming if you had this going on, pH would be the least of your concerns.

FunkEngine · Nov 3, 2017

Brew12 said:
I used to have a chart showing CO2 concentrations as they relate to pH and Alk but I can't find it.

If I were you, I would run a quick and easy test. Get a sample of water from your aquarium and take it outside along with an air pump/air stone. Let it aerate for a few minutes then bring it in and put your pH probe in it. If it doesn't read at least 8.2 you know your probe isn't reading accurately.

If you don't have an air pump you can do almost the same thing using a larger container and a whisk. Just whisk it up good and fast to try and get lots of air exchange.

The only other thing that would make sense for your pH to be this low would be if you had a lot of bacteria in your system that were consuming oxygen and releasing CO2. I am assuming if you had this going on, pH would be the least of your concerns.

In the indirect CO2 test, will it matter if the outside temperature is vastly lower? I'm going to assume I need to let it warm back up when I bring the sample back inside for measurement.

Brew12 · Nov 3, 2017

FunkEngine said:
In the indirect CO2 test, will it matter if the outside temperature is vastly lower? I'm going to assume I need to let it warm back up when I bring the sample back inside for measurement.

It will, although I honestly don't know by how much. I think letting it warm back up would be a smart move. As long as the sample is relatively still you shouldn't get much air exchange while you wait.

Dennis Cartier · Nov 3, 2017

Another option is to get a CO2 monitor for measuring the CO2 content in your home. That will help to rule out CO2 as being the cause. I go through the ins and outs of using one in this thread https://www.reef2reef.com/threads/monitoring-indoor-co2-level.334377/.

Dennis

Randy Holmes-Farley · Nov 3, 2017

How cold are we talking about?

FunkEngine · Nov 3, 2017

Randy Holmes-Farley said:
How cold are we talking about?

Today its about 30F, so not bitter cold, but significantly lower than my tanks 78F.

FunkEngine · Nov 3, 2017

Dennis Cartier said:
Another option is to get a CO2 monitor for measuring the CO2 content in your home. That will help to rule out CO2 as being the cause. I go through the ins and outs of using one in this thread https://www.reef2reef.com/threads/monitoring-indoor-co2-level.334377/.

Dennis

I've considered one, but honestly I don't think its worth the cost. A scrubber set up would be less, and it would either fix the problem, or not which would basically give the same information as the CO2 monitor.