HELP High PH Readings

Jyetman · 03/29/2017, 04:48 PM

So my pH is rising to 8.56 by mid day. I'm having a terrible time maintaining ALK above 7 DKH. Dosing KALK to maintain the ALK and CA (500PPM) tried slowing the drip rate. Corals look better but high PH and ALK is still low. I read its the high pH causing the low ALK. Tried their recommendation of adding 1 ML white vinegar per gallon to lower pH. So my 75 Gallon Reef I took a cup of tank water and inserted 10 ML to slowly add see what happens. The ph immediately dropped to 8.50 but is slowly going back up again. What or how do I do this properly?

Optionman · 03/29/2017, 05:36 PM

Is your ph stable, even if on the high side at its peak? I'm sure it drops to 8.2ish at night, or some similar range. If corals look good and you have a stable ph range, I wouldn't mess with it. Every system stabilizes differently, my 150g mixed reef for example is stable at Alk 11, CA 450, ph 7.9-8.1ish. Just my two cents. Good luck.

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bertoni · 03/29/2017, 05:54 PM

Adding vinegar will lower the pH temporarily, but it can feed bacterial blooms and cause other problems. I would avoid using it to control pH. In an emergency, a bit of seltzer water can lower the pH the same way without feeding bacteria, but 8.56 is not high enough to be an emergency.

I'd get a second opinion on the pH measurement. Measurement problems are very common. Meters can have issues with calibration or electrical interference, for example.

If the pH reading is correct, the problem likely is a low carbon dioxide level in the tank. Kalk can raise the pH quite a bit, so I'd consider switching to baking soda and calcium chloride (as a DIY 2-part) for a bit, or buying a low-pH commercial product. Aeration can cause this problem, too. Getting good motion on the water surface and tuning the skimmer can be help in some cases, although that seems to be rare. It's easy to check for surface films, though.

Jyetman · 03/29/2017, 06:40 PM

Ok so I recalibrated the new pinpoint probe and its reading now 8.36 which seems closer to the 8.40 API High PH reading. When I put the old probe in the KALK reservoir it reads 11.4 thought KALK PH goes no higher than 10 DKH correct?

bertoni · 03/29/2017, 07:27 PM

Saturated Kalkwasser has a pH of about 12.5. I suspect your Kalkwasser is close to that, but that the pH meter can't read accurately at that level. Mine never could, anyway. 8.36 is an excellent pH level.

http://reefkeeping.com/issues/2005-01/rhf/index.htm#12

03/29/2017, 05:54 PM	#3
bertoni RC Mod Join Date: Mar 2002 Location: Mountain View, CA, USA Posts: 88,616	Adding vinegar will lower the pH temporarily, but it can feed bacterial blooms and cause other problems. I would avoid using it to control pH. In an emergency, a bit of seltzer water can lower the pH the same way without feeding bacteria, but 8.56 is not high enough to be an emergency. I'd get a second opinion on the pH measurement. Measurement problems are very common. Meters can have issues with calibration or electrical interference, for example. If the pH reading is correct, the problem likely is a low carbon dioxide level in the tank. Kalk can raise the pH quite a bit, so I'd consider switching to baking soda and calcium chloride (as a DIY 2-part) for a bit, or buying a low-pH commercial product. Aeration can cause this problem, too. Getting good motion on the water surface and tuning the skimmer can be help in some cases, although that seems to be rare. It's easy to check for surface films, though. __________________ Jonathan Bertoni

03/29/2017, 07:27 PM	#5
bertoni RC Mod Join Date: Mar 2002 Location: Mountain View, CA, USA Posts: 88,616	Saturated Kalkwasser has a pH of about 12.5. I suspect your Kalkwasser is close to that, but that the pH meter can't read accurately at that level. Mine never could, anyway. 8.36 is an excellent pH level. http://reefkeeping.com/issues/2005-01/rhf/index.htm#12 __________________ Jonathan Bertoni

03/29/2017, 04:48 PM	#1
Jyetman Registered Member Join Date: Nov 2012 Location: Phoenix, AZ Posts: 1,712	HELP High PH Readings So my pH is rising to 8.56 by mid day. I'm having a terrible time maintaining ALK above 7 DKH. Dosing KALK to maintain the ALK and CA (500PPM) tried slowing the drip rate. Corals look better but high PH and ALK is still low. I read its the high pH causing the low ALK. Tried their recommendation of adding 1 ML white vinegar per gallon to lower pH. So my 75 Gallon Reef I took a cup of tank water and inserted 10 ML to slowly add see what happens. The ph immediately dropped to 8.50 but is slowly going back up again. What or how do I do this properly?

03/29/2017, 05:36 PM	#2
Optionman Registered Member Join Date: Apr 2016 Location: NJ Posts: 774	Is your ph stable, even if on the high side at its peak? I'm sure it drops to 8.2ish at night, or some similar range. If corals look good and you have a stable ph range, I wouldn't mess with it. Every system stabilizes differently, my 150g mixed reef for example is stable at Alk 11, CA 450, ph 7.9-8.1ish. Just my two cents. Good luck. Sent from my iPhone using Tapatalk

03/29/2017, 06:40 PM	#4
Jyetman Registered Member Join Date: Nov 2012 Location: Phoenix, AZ Posts: 1,712	Ok so I recalibrated the new pinpoint probe and its reading now 8.36 which seems closer to the 8.40 API High PH reading. When I put the old probe in the KALK reservoir it reads 11.4 thought KALK PH goes no higher than 10 DKH correct?