pH stuck at 7.9 and refuses to budge

[2ndTimeCharm]

Sorry, have not filled out my profile yet...tank has only been running 2.5 mos and haven't needed to post yet.

Basement 75 gallon tank, 35 gallon sump, 2x 4" 200 micron socks, Octopus 160 skimmer, ATI Powermodule T5s, ~60 lbs live rock, light bioload (2 Percola, 1 damsel, 4 peppermint shrimp, ~ 10 snails). BRS Phosphate reactor with 1 mo old PhosBan GFO.

Mag 9 return, Korallia 4 + Korallia Evo 1050.

Corals: Acropora frag, Monti Cap frag, Unknown Acro/Monti frag, Green sinularia, various buttons/polyps/leathers. All on the small side.

Coralline growing slowly.

For month 0-2 I used Brightwell A+B, Seachem Reef Builder for calcium/alkalinity. Used Seachem builder in topoff, low dose.

Had an overgrowth of brown algae, unsure of type, about 3-4 wks ago, hit it hard with 3-4x Kalk slurry treatments per day for 2 days, pushed pH up to 8.7, brown algae successfully killed off.

Since algae incident, have stopped using SeaChem Reef Builder in topoff, have used Brightwell Calcion and Reef Builder intermittently to maintain alk and calcium.

Have done 2x 10% water changes since then (every other week) with Tropic Marin. Using RODI water with 1 PPM TDS.

Friday I recalibrated my pH monitor (Milwaukee) and I THOUGHT I had been running at 8.2-8.3 for months, turns out I am at 7.9 am, 8.0-8.1 daylights.

Since then, I have dosed the max dose of Seachem Reef Buffer x2 days, and dripped 1 gallon per day of Brightwell Kalk 2 at 2 tsp/gallon. pH locked in at 7.9/8.1

Mag was 1130 this morning, added max dose of Brightwell Magnesion, have not retested, Total alk (SeaChem Reef Status) this AM was 3.2, added 1.5 TSP SeaChem Builder, so Alk should be around 3.4 but have not re-tested since this morning. Calcium this morning was 395 (Salifert), dosed max BrightWell Calcion, based on my experience its safe to say calcium though not re-tested should be 435 right now.

I have just added the max dose of Kent Super buffer, and pH went from 7.9 to 8.0 back to 7.9.

I am going batty.

1) Is it possible I have high indoor CO2 levels?

2) Why are my tank params not responding AT ALL to the Kalk +2?
I thought tanks with high CO2 are supposed to respond to Kalk, as per Farley article?

Thanks in advance for any/all advice,

 

[Boomer]

And you will continue to go batty if you keep adding buffer to raise the pH

Your Alk is fine STOP dumping in buffer. You have a slight high room air CO2 issue. Kalk will respond to CO2 but you keep adding in buffer. When that buffer is added it also adds in CO2 and lowers the pH. Buffer is for ALK and NOT pH. All the buffer in the world will not help pH when there is CO2. It will raise the pH but it will them just drop back down.

pH locked in at 7.9/8.1

That is fine LEAVE it alone.

If all was perfect with the CO2 in your house the pH would be ~ 8.35 and that 8.35 is due to the higher Alk ~ 3.2 meq / l. If we dropped your Alk down to NSW Alk of 2.33 meq / l your pH should be 8.25.

 

[AlohaTropics]

If there is a way to keep a window cracked by the tank or by the sump, you will see a big increase in pH. If you can't do that (tough in the winter), you can alternatively run your protein skimmer's airline outdoors.

 

[NL146]

If there is a way to keep a window cracked by the tank or by the sump, you will see a big increase in pH. If you can't do that (tough in the winter), you can alternatively run your protein skimmer's airline outdoors.

Does a longer airline impact on the performance of the skimmer in any way?

 

[DJYoshi]

If there is a way to keep a window cracked by the tank or by the sump, you will see a big increase in pH. If you can't do that (tough in the winter), you can alternatively run your protein skimmer's airline outdoors.

what if I'm using a HOB skimmer (mag 3 driven remora) and it's too damn cold to crack the window?

 

[2ndTimeCharm]

what if I'm using a HOB skimmer (mag 3 driven remora) and it's too damn cold to crack the window?

So other people are seeing this too?

It just started getting cold enough to keep windows closed about 3-5 days ago.

Never trust your LFS blindly or you will walk home with armfuls of additives you don't need.

I just did a 20% WC with SeaChem Reef, hoping that will test a little better tomorrow.

I just don't understand why the BW Kalk +2 does nothing to my water params; Kalk should be able to boost my pH a couple points easily.
Thoughts?

 

[Boomer]

If one can not open windows or does not have a HVAC and they pH is out of line with CO2 and Kal is not making it happen then one can get Sodium Hydroxide form SeaChem labs as their Aquavitro Balance. This is the same as Kalk but without the calcium. So, do not expect to much more over kalk.

The ideal is what we call a CO2 scrubber, that takes out the CO2 entering your tank as it is sucked in by the skimmer. These units can raise the pH 0.3 pH. A single canister fill should last 2-3 weeks.

http://thefilterguys.biz/skimmer_media.htm

Another option is a DIY liquid CO2 scrubber of a NaOH (Sodium Hydroxide)or Ca(OH)2 kalk slurry. You get a container with a snap-on air tight lid and fill it 3/4 with RO/DI water and add the SH or Kalk to saturation. An air line is then feed into the side, near the bottom. A second line comes out just under the lid. As the air goes in it bubbles up through the slurry water...........

CO2 + NaOH --- > HCO3- + Na+

where this CO2 free air fills the underside of the lid 1/4 air pocket. The CO2 free air rising out of the slurry will pressurize the container and rise out of the lid effluent tube to the skimmer.

 

[Boomer]

I just don't understand why the BW Kalk +2 does nothing to my water params; Kalk should be able to boost my pH a couple points easily.
Thoughts?

I already explained that. STOP adding buffer and use the Kalk drip ONLY and only add buffer when needed. Also, is your kalk drip saturated ? Meaning, a pH ~ >12

 

[2ndTimeCharm]

I just don't understand why the BW Kalk +2 does nothing to my water params; Kalk should be able to boost my pH a couple points easily.
Thoughts?

I already explained that. STOP adding buffer and use the Kalk drip ONLY and only add buffer when needed. Also, is your kalk drip saturated ? Meaning, a pH ~ >12

Never measured pH on my incoming Kalk; using 2 tsp/gallon which I understand is saturated, via airline drip.

 

[Boomer]

Yes, 2 tsp / gal is correct. But it best to check the pH which is 12.45.