If its not CO2, then why low pH

[Biologic]

So chasing the dragon here -- can't get above 8.01 units

>Surface Agitation --- NO EFFECT
>Opening windows --- NO EFFECT
>Running an oversized recirculating CO2 scrubber --- NO EFFECT
>Running line outside of the house, with recirculating skimmer --- NO EFFECT
>Keeping alkalinity rock steady --- NO EFFECT
>Combining everything above --- NO EFFECT
>Reading Randy's Article --- NO EFFECT

>Kalkwasser drip --- obvious positive effect but difficult in an 28 gallon all-in-one

What I haven't tried --

>Using soda ash for alkalinity -- I use ALL4Reef Calcium Formate at a rate of 15.5 mL per day.
>refugium, difficult to add on an AIO.

POSSIBLE Contributing Factors ?? --

>Two small damsels, one small clown, one small pseudochromis, 10 snails, mostly SPS
>Calcium Formate? Maybe? That's the other thing I can think of at this point
>Decay of bacterial population contributing to depressed pH

Concerns --

Since I stopped using kalkwasser a month ago as my primary method of calcium and alkalinity supplement due to safety concerns and limited ability to control the dose, my pH has been in the pits. 7.65 at night. Yes I've calibrated my probes, and checked them against some standard solutions. I am at a lost.

My sps have definitely stopped growing since I switched from kalkwasser. My alkalinity consumption has slowed down.

 

[Jekyl]

Co2 scrubber could work

 

[Biologic]

Co2 scrubber could work

I tried that, I detailed it in the post. I even ran the air for the intake for the CO2 Scrubber outside. No effect.

Unless it's not hooked up correctly. I doubt it.

 

[Jekyl]

I tried that, I detailed it in the post. I even ran the air for the intake for the CO2 Scrubber outside. No effect.

Unless it's not hooked up correctly. I doubt it.

Oops sorry. Missed the scrubber part.

 

[ScottB]

You have a skimmer, a scrubber, and probes all hooked up to an AIO 28g tank? Impressive.

How about a pH reading chart so we can look for some pattern? 7.65 is super low so that is my first line of questioning. What probe are you using?

 

[mdb_talon]

Based off everything you have tried my bet is on bad/needing calibrated PH probe.

As i understand it alkalinity and co2 concentrations determine PH and nothing else. If that is the case then your alk is very low, your co2 is high, or your reading are wrong. Maybe it is not as simple as i think, but that is how i understand it anyway.

 

[capted]

What are you using for measuring ph? Asking because I had issues with electrical interference causing a low ph reading with my Pinpoint's.

 

[Biologic]

You have a skimmer, a scrubber, and probes all hooked up to an AIO 28g tank? Impressive.

How about a pH reading chart so we can look for some pattern? 7.65 is super low so that is my first line of questioning. What probe are you using?

Based off everything you have tried my bet is on bad/needing calibrated PH probe.

As i understand it alkalinity and co2 concentrations determine PH and nothing else. If that is the case then your alk is very low, your co2 is high, or your reading are wrong. Maybe it is not as simple as i think, but that is how i understand it anyway.

Apex pH probe. Freshly cleaned in 5% HCl and re-calibrated. I can mix fresh saltwater and it will read 8.2+ pH units. The results are a normal di-urnal pH rise and fall.

I can also confirm with a simple pH test with Salifert. Yellowish-Green.

Alkalinity is tested via Hanna 7.5 to 8.0 dkH. I also use Salifert titration 0.48 mL's used for titration results is ~8.0 dKH.

Unless Calcium formate alkalinity reads differently?

 

[Biologic]

What are you using for measuring ph? Asking because I had issues with electrical interference causing a low ph reading with my Pinpoint's.

My grounded my tank. Not sure if that makes a difference, but I test the probe outside the tank in fresh mix saltwater, I get 8.2+

 

[gentlefish]

That’s odd. You would think that CO2 is the main contributor. But than again thanks for all the info. Did you try to degas tank water outside to see what pH would be, it would just be another test to confirm what you already did.

 

[gentlefish]

Sorry missed your last post by a second.

 

[Biologic]

That’s odd. You would think that CO2 is the main contributor. But than again thanks for all the info. Did you try to degas tank water outside to see what pH would be, it would just be another test to confirm what you already did.

I haven't tried that. Thank you for the suggestion. I need to get a portable pH probe and try that.

 

[capted]

Did you try testing your water in a container (probe not in the tank or sump)? Although you did say you checked it with the salifert.

 

[Biologic]

Did you try testing your water in a container (probe not in the tank or sump)? Although you did say you checked it with the salifert.

That's been suggested and that's the only thing I've yet to do. I really would like to test that with my existing probe and a new pH probe to see what the heck is going on.

 

[Biologic]

Just reconfigured my CO2 scrubber in a different way to see if that will make a difference. I've seen a couple different ways, but this way will only use and scrub the existing air into the system. I've done this before, but the issue is that it makes the skimmer kind of screwy and raises the water level overtime, which takes about 4 hours. I did this at 2 AM this morning.

So yes I am losing sleep over this.

The probe is the only remaining issue that needs to be fully disproved. I need another reliable probe to test against.

 

[capted]

Sounds like a plan. I was going crazy over the same issue with 2 pinpoint meters and new probes. Calibrated perfectly in the standards but read my tank at 7.8. Funny thing was at night the ph went up!! Long story short, it turned out the problem was one of my led light power blocks. I caught it one night when it was going through a dimming cycle and both meters were jumping all over the place!! Crazy as that sounds. Replaced it and now the meters read stable.

 

[BoxKing]

Go back to using kalkwasser until you find a method of dosing you feel safe with if youre that concerned about your PH. Your probe is probably fine. I have every HANNA Checker made, and I could have found a better use of the $50 now that I don’t bother checking my PH (used maybe twice.)


IMHO, I’d be more concerned with your ALK swing from 7.5-8... I’d seek out a ALK # around 8.5. Control your ALK and your PH follow. As far as the Holy Trinity, AlK CALC MAG... I only regularly test my ALK, and dose accordingly to keep ALK stable (equal dosing of CALC) - 10% water change for MAG biweekly.

 

[Rjmul]

Make one of these (or buy it, I chose to make it.

Run it this way_____ doser pulls from ATO container. Pushes RO water into "device" device pushes saturated kalk into tank.

dose kalk As well as whatever else your using. But Max your kalk out first

my PH is sitting around 8.3 in a two bedroom apartment with three if not four people home (and breathing) at all times. I think I could push that PH higher but time will tell me

I keep editing this, don't waste your time or money on something that has to be maintained as much as a co2 scrubber. For me, space is limited. I don't want to store huge bulk buckets of co2 media. Just dose kalk. Best part is, I can LOAD that little beaker up with like a straight cup of kalk. Saturated is what saturated does

 

[monkeyCmonkeyDo]

Dang i.liked ur.post till u said u dose.equal parts.cal. lol
D

 

[Biologic]

Go back to using kalkwasser until you find a method of dosing you feel safe with if youre that concerned about your PH. Your probe is probably fine. I have every HANNA Checker made, and I could have found a better use of the $50 now that I don’t bother checking my PH (used maybe twice.)


IMHO, I’d be more concerned with your ALK swing from 7.5-8... I’d seek out a ALK # around 8.5. Control your ALK and your PH follow. As far as the Holy Trinity, AlK CALC MAG... I only regularly test my ALK, and dose accordingly to keep ALK stable (equal dosing of CALC) - 10% water change for MAG biweekly.

That's the biggest swing I've had in a while which was recent. I had pump issue, but that's resolved. Otherwise its 7.7 dKH units. There is no swing otherwise from day to night that I've observed. As far as I can tell, alkalinity is not a contributing issue. Magnesium is also supplemented in All4Reef, but I make the DIY recipe, and cut the magnesium in half. I do a weekly 15% water change.