Is 7.7 pH bad?

Fizzman

New member
K so 24g nano with about 19gal of actual water volume.
Parameters using Api test kit
Alk 12dkh
Ca 460
Mag 1425
Sg. 026
Phosphates between zero and 0.25(closer to zero)
Nitrate zero
PH 7.7 on phtestr 10 digital meter
I am running an upflow ATS(started it about a week ago)


Today is first day I took pH reading since I just got new batteries for the meter. My pH is 7.7 1 hr before lights on and 7.8 1hr before light off. The ATS is on reverse light cycle but there's hardly any algae so I doubt it's maintaining the pH at 7.7 when main lights are out. My guess is that the air bubbler for the ATS is mixing in CO2 from the room. Anyone want to chime in on if this logic is correct or know of other potential causes.

The main question is though, is a constant 7.7ph bad since it is on the low side for calcification. Tank is about 2.5 months old. Mixed reef
 
Is possible that the air bubbler or a skimmer to lower you ph .You could aerate the room more and even start using kalk in the top off water but first get a lower alk.Or you could mount the air pump to draw clean air from a room or even from outside the house if its not too cold .
 
A couple of questions. Does the PH meter you are using have a calibration function? If so have you calibrated it? Just want to make sure the PH you are reading is in fact the true PH.

At PH 7.7 calcium carbonate starts to dissolve. So this is the lower bound of acceptable PH for a reef tank. Typical causes are too much CO2 in the inside air in your home. You can test for this by taking a cup of tank water outside and using an air stone (outside) to aerate the water for an hour or so and see if the PH goes up. Again a calibrated meter would be recommended. Opening a window close to the tank and again observing the PH over several hours is another method of determining if the CO2 level is contributing to low PH.

I would not get too caught up in chasing PH until you know that your meter is providing an accurate reading.
 
7.7 is a bit low, but a lot of Tanks of the Month have run at 7.8. I might make sure that there's a good rippling surface on the water surface, but I agree that the most likely issue is carbon dioxide in the room.
 
It does have a calibrate function. It comes with pH 7 tablets. But I don't have RODI water. Do you think bottled water would work just fine? It says "purified water with minerals added for taste" probably not huh?
 
So I put a cup with the bubbler outside for an hour. PH is 7.9 while pH inside tank is 7.6, so not sure if it's purely the co2 causing it. I'm gonna buy some calibration solution and hopefully the meter is .2-.4 lower. But hypothetically let say the meter is accurate? Even running the air pump outside didn't change it drastically considering my dkh is 12. There is a .3 difference but is that significant? No real way to fix pH without adding Alk right?
 
You need RODI water or best would be distilled water from the drug store.That purified water with minerals added is RO water that has added somme calcium,magnesium, etc ,and is a bit alkaline.Your ph issue is clearely from the air that has too much CO2 in it and also the ph meter is not well calibrated.If you want to use kalk in the top off water to have a higher ph i would reccomend first to change the salt (12 alh i think you use coral pro) with a salt that has an alk more cloose to the alk of the ocean ,7(if you use red sea salt then the blue bucket is what you want,it has lower alk).
 
So I put a cup with the bubbler outside for an hour. PH is 7.9 while pH inside tank is 7.6, so not sure if it's purely the co2 causing it. I'm gonna buy some calibration solution and hopefully the meter is .2-.4 lower. But hypothetically let say the meter is accurate? Even running the air pump outside didn't change it drastically considering my dkh is 12. There is a .3 difference but is that significant? No real way to fix pH without adding Alk right?

Sure you can run a hose from outside to your tank to feed your protein skimmer air intake, or an air stone if you have no protein skimmer. Depending on where your tank is located this may be possible or not. If you can do it, that will give you a lift of .3, which is a decent rise.

You are correct about Alk, no point in using any of the PH lift products as they will spike your Alk, which is already 12 dkh.

I would suggest getting your PH meter calibrated is job #1 at this point. If after you calibrate you find that it was too low by .3, then you are fine, and using an outside air supply becomes a nice to have.

Dennis
 
I use Catalina water, and I have been dosing baking soda. I actually was targeting 10dkh but then it went to 12dkh but decided it wasn't too bad so I left it there. Running the pump outside isn't possible for me because of where the tank is. Maybe the Catalina water is lower pH than normal, I'm gonna check.
 
I use Catalina water, and I have been dosing baking soda. I actually was targeting 10dkh but then it went to 12dkh but decided it wasn't too bad so I left it there. Running the pump outside isn't possible for me because of where the tank is. Maybe the Catalina water is lower pH than normal, I'm gonna check.

Im not sure about now but alot the local stores stopped carrying catalina due to phosphates and other issues years ago, may have been corrected by now though. Also had the same issue, lower and inconsistent ph among other elements.
 
I should also mention all of the stuff I use to dose in case any of it is contributing. I use calcium chloride (homebrew food grade) for calcium, baking soda for Alk, and Epsom Salt for Mag. I don't mix it with water, I just put it in dry on the back side of my 24g nano at the inlet. I break up the calculators dose into like 3. Calcium chloride never more than half a tsp at a time, baking soda never more than 1/4 tsp at a time, and Epsom Salt never half a tbsp at a time.
 
I'm in southern California and it seems that's all that Lfs carry when u buy sw. It's cheap though, 0.40/gal. I don't have an RODI unit, but seems like it would cost about the same if not more expensive if I mix my own water. Instead I just bought 4x5gal water jugs and buy a month supply at a time (5gal per week) for now and when my tank is older should be a 2 month supply.
 
So I put a cup with the bubbler outside for an hour. PH is 7.9 while pH inside tank is 7.6, so not sure if it's purely the co2 causing it. I'm gonna buy some calibration solution and hopefully the meter is .2-.4 lower. But hypothetically let say the meter is accurate? Even running the air pump outside didn't change it drastically considering my dkh is 12. There is a .3 difference but is that significant? No real way to fix pH without adding Alk right?
Actually, that's a significant change. The normal aeration period is 3 hours or so. I'd try again and leave the cup for 3 hours. This article discusses how to make a pH sanity check solution:

http://web.archive.org/web/20021015005420/www.animalnetwork.com/fish2/aqfm/2000/feb/bio/default.asp

There's nothing you can dose to fix the pH that does not add alkalinity, and even the high-pH alkalinity supplements only have a temporary effect.
 
So I just tested the sw that I have. 8.0 pH 10dkh. And currently running bubbler outside again for 3 hrs and see what the pH is. This explains why I got 12dkh when trying to aim for 10dkh. I thought I was working with 7dkh nsw. I'll be sure to test each batch next time
 
If you can't run an airline to the outside or don't want to due to pollutants then you could build a cheap CO2 scrubber.

A bottle with small holes underneath, airline to the skimmer, and some sodalime.

I get my sodalime in 5lbs from MedVet online. Depending on the skimmer I like to T off and a ball valve before the skimmer so the sodalime isn't feeding 100% of the air. Some skimmers pull a lot of air and could deplete the Sodalime quickly.

I'd also do a 7 and 10 calibration on that pH meter.


Edit: here's how I have mine setup fwiw
http://www.reefcentral.com/forums/showthread.php?p=24679460
 
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Co2 scrubber is good to use it on a protein skimmer but its a bad idea to use it in an algae scrubber.Algae needs co2,thats the purpose of aeration of the upflow scrubber.
 
Yeah, I don't have a skimmer

Could still be used with an air stone but a skimmer would provide a lot more aeration and less messy. I would also suspect the CO2 scrubber would be just fine with the upflow ATS. The bubbles are to create flow and the algae will get it's carbon from the water not the air bubbles.
 
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So a co2 scrubber is basically air passing through it before going into the water? I'm gonna research more on co2 scrubbers
 
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