Low PH

AirIck

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My PH tops out at 7.6 (Apex is the only thing I have to test. All other parameters are stable and perfect, as long as I do weekly water changes. Corals are fine, just not growing at the rate I’d like.

if I dose Kalk would this throw off my Alk and Cal numbers?

should I consider a c02 scrubber instead?
 

Randy Holmes-Farley

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I would confirm that number before trying to fix what might be a test error.

Aquarium controllers are quite prone to pH measurement issues of various sorts, and that number is low enough to either be test error, or a really substantial CO2 issue (or both).
 

MnFish1

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My PH tops out at 7.6 (Apex is the only thing I have to test. All other parameters are stable and perfect, as long as I do weekly water changes. Corals are fine, just not growing at the rate I’d like.

if I dose Kalk would this throw off my Alk and Cal numbers?

should I consider a c02 scrubber instead?
1) have you calibrated your meter lately?
2) Do you notice that if you open the windows near the tank that the pH rises (if so - a Co2 scrubber should help)
3) Even with calibration - I would tend to use another method to verify the Apex reading.
4). Do you dose anything now? If so - using Kalk will increase both your alkalinity and Calcium - unless you adjust the dosing of the other items. pH is more a function of decreasing CO2 as compared to adding a chemical in my experience.
 

Righteous

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My Apex meter is VERY hard to calibrate. I use a Hanna HI 98100 which I calibrate with 7 and 10 solution which is a lot more accurate. The Apex probe is consistent, at least, so I just subtract the difference and check it around once a month with the Hanna.

 

arking_mark

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My Apex meter is VERY hard to calibrate. I use a Hanna HI 98100 which I calibrate with 7 and 10 solution which is a lot more accurate. The Apex probe is consistent, at least, so I just subtract the difference and check it around once a month with the Hanna.


Wouldn't recommend this...

±0.2 pH accuracy
 
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Righteous

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Assuming one can trust the certification:

F683CE60-2881-44A4-8C2C-0534230CDE6D.jpeg
 

arking_mark

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It's accuracy is listed as +/- 0.2 pH. If that’s good enough for you, then by all means use it.


Resolution of 0.1 pH with an accuracy of +/-0.02
 
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Righteous

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I stand corrected.

You’ve got me concerned now though! o_O I see the +/- 0.2 accuracy on that page, which I am assuming is a typo. I’ve been going off the specification details and what I remember when I bought it. I also assumed they wouldn’t make a 0.01 resolution if the accuracy was that bad but who knows. Maybe I should get the Milwaukee and compare.
 

Righteous

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calibrating teh apex probe is extremely easy - you buy the solutions and calibrate it - you cannot IMHO - accurately do it the way you're attempting

I’m not sure if this is a misread or wrong thread post here… I didn’t suggesting calibrating it in any manner, and I don’t think the OP mentioned he had calibrated it at all. Definitely with a reading of 7.6 that’s probably the first and easiest thing to do.

i think we were just all agreeing having a second method to verify the apex reading is best.
 
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MnFish1

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I’m not sure if this is a misread or wrong thread post here… I didn’t suggesting calibrating it in any manner, and I don’t think the OP mentioned he had calibrated it at all. Definitely with a reading of 7.6 that’s probably the first and easiest thing to do.

i think we were just all agreeing having a second method to verify the apex reading is best.
Sorry - I think it was a mis-read (I wasn't clear). I was under the impression that you said you were using a hanna checker, calibrating the hanna with 7 and 10 pH and then somehow adjusting your apex pH by a factor of some kind (that was my impression after reading your post at least). I was saying I don't think you should do it this way - and that the best thing to do is to just calibrate the Apex Probe. The apex and your second method should always agree - if not - you have no way (without doing a third test) - to know 'which one is right'
 

Uncle99

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While I am a “number chaser” PH is the only one I don’t test for.
Pretty hard to get a 7.6 unless there is no air flow and lots of breathers in the room with the tank.

In the case of PH, I am a “number maximizer” meaning I employ those things which are relatively easy and cost effective to implement.

PH Probes IMM are next to useless over time and provide results which at times, seem hard to believe.

So I just:
I don’t use a lid.
I keep a ton of surface movement.
I bring outside air into my skimmer.
I blow a fan across the surface after lights out.
I dose alk only during lights out.
I dose carbon only during lights on.

After running this for a month, API said 8.2-8.3.

I have never tested it again.
 

josephxsxn

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You should door an outdoor airstone test imho and additionally another test to confirm the number your apex gives.

I never had much luck with opening the windows but some people do... Another option rather then a co2 scrubber is running an outdoor airline to your skimmer.
 

Righteous

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Sorry - I think it was a mis-read (I wasn't clear). I was under the impression that you said you were using a hanna checker, calibrating the hanna with 7 and 10 pH and then somehow adjusting your apex pH by a factor of some kind (that was my impression after reading your post at least). I was saying I don't think you should do it this way - and that the best thing to do is to just calibrate the Apex Probe. The apex and your second method should always agree - if not - you have no way (without doing a third test) - to know 'which one is right'

okay yeah.. hopefully I didn’t confuse anyone because I wouldn’t recommend that for the reason you stated. I basically assume the Hanna is more accurate, but I kind of just use the measures as an upper/lower bound and sanity check. They’ve always maintained about 0.3pH difference. If that started drifting significantly then I’d know I had an issue with one.
 

MnFish1

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okay yeah.. hopefully I didn’t confuse anyone because I wouldn’t recommend that for the reason you stated. I basically assume the Hanna is more accurate, but I kind of just use the measures as an upper/lower bound and sanity check. They’ve always maintained about 0.3pH difference. If that started drifting significantly then I’d know I had an issue with one.
I would suggest - that its impossible to know whether its your hanna thats 'correct' or your apex. Unless you calibrate the apex.
 
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