Alk and pH

D

DaveJ

Just had some rather direct experience with the relationship between Alk and pH levels.

A little background.... I have been having some difficulties maintaining a steady pH level. It never gets out of hand, mainly because I won't let it, but it has caused me some mild frustration. One of the direct relationships that contribute to a low pH is lower Alkalinity. While my levels were within good guidelines it was towards the lower end of that scale. So I decided to bump my Alk level to the upper mid level around 9.5 dKH and low and behold my pH has risen and is much more stable. I am going to push it up a bit more this weekend to the 10.5 or 11 range and will then maintain it there.

To give you an idea.. I was typically running pH 8.20ish during the day and 7.8ish at night. Still acceptable but a bit of a swing. I would dose Kalk to steady it overnight as well. My dKH ran around 7.0 - 7.5ish....

After bumping the dKH up to 9.5 ish its now been steady at 8.20 and we will see the low tonight.

So.... while this isn't new information, it certainly provides some real life examples of how Alk can mess with your pH levels.

Incidentally, my MG is steady around 1200ppm.
 
IMO it is DKH or alkalinity that holds up PH it is THE factor not just one...alkalinity is the measurement of being above 7.0 PH (neutral)
alk in reefs should be 2.9 - 4.0 meqs/liter or 8-12 DKH
-so an optimum number is 10DKH any lower than about 8.5 and the PH can swing down - we run some tanks thick with salinity and even 11+ is OK
-no need to drip Kalk anymore or do a juggling act unless you feel like it!!
 
@Frogspawn wrote:
What method do you use for bumping up the Alk? I'm still figurin' this stuff out.... heh said:
Kent Reef Buffer... 3 heaping tablespoons (mixed in RO) for approx 220 total water volume. I'll use B-Ionic 2-part (alk solution only) for the fine tuning up to 10.5 or 11.

Then its a matter of replacing what the tank uses up in Ca Alk and Mg.

I love kalk but the limitation of it is that it bumps CA and alk at the same time. So when you get one out of balance, you need to look elsewhere, hence the two part additives.

I'm still debating with myself on going to DYI Two Part or sticking with the Ca Reactor now that I have my pH issue resolved (knock on wood).
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@Neptune1 wrote:
IMO it is DKH or alkalinity that holds up PH it is THE factor not just one...alkalinity is the measurement of being above 7.0 PH (neutral) alk in reefs should be 2.9 - 4.0 meqs/liter or 8-12 DKH -so an optimum number is 10DKH any lower than about 8.5 and the PH can swing down - we run some tanks thick with salinity and even 11+ is OK -no need to drip Kalk anymore or do a juggling act unless you feel like it!! said:
I don't disagree, but also the mg and ca levels play a role in that too... primarily the relationship between them. If your MG is low, you will have a hard time maintaining proper levels and if your ca is low the others are tougher to maintain etc...
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true, true...but alk at level is the KEY... the relationship between Ca and Mg create an "ionic balance" and its much more stable then. but in a tank with a DKH of 10.5-11.0 its "rare" to see a low PH .
and if it is then Ca is probably low too. not in balance
- ive seen a DKH of 7 and PH of 8.3 ...but Calcium was at 540 and helping to hold up the foundation... i read somewhere that calcium in in RO in balance is 8.6 PH by itself ( and Kalk is thru the roof being hydroxide) - like if you put them in RO water individually what would the PH be...
-we were studying all the alkaline minerals contained in sea water and using samples to base the fact that true PH of saltwater to be 8.3 because of the mix of 70 trace elements that give different "individual" PH readings
-the major ones we target kinda keeps " all 5 ducks in a row" for us.
 
Well, I for one keep my alk at 11 and still have problems with pH. My Mg is around 1400 and Ca is 425. My house is very well insulated so I have to battle higher CO2 levels as well.
 
Gravit, are you ADDING CO2 thru cal reactor or what??? your skimmer should gass off most of the build up you may have and carbonic acid shouldnt be forming... do you run only closed loop or Berlin / plenum method or what??? surely you dont have enough carbon dioxide from breathing in your home to cause PH swings!!! you better open a window or something!! by swings do you mean 8.2 or alot lower??
 
@Neptune1 wrote:
Gravit said:
Nope, I haven't taken the plunge for a Ca reactor yet, so no CO2 is being added there. Berlin method all the way! I have a large skimmer for this size tank and it pulls in a very high amount of air.

Many homes have enough CO2 concentration in the air to cause pH swings..this isn't such an odd thing. Opening a window, when the weather permits, tends to raise my tanks pH by .20 to .50. As for swings, I'm talking 7.6 at night and 7.8 during the day if I don't drip kalk 24x7. I use a pH meter that is calibrated once a month, probe was replaced about 3 months ago.

For comparison, my last house was built in 1950 and was drafty as mosquito netting and my pH rarely went below 8.0.
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Baked baking soda mixed in RO water will bring that pH up, Kevin.
 
@GraviT wrote:
[I]@Neptune1 wrote:[/I][quote="Gravit said:
Nope, I haven't taken the plunge for a Ca reactor yet, so no CO2 is being added there. Berlin method all the way! I have a large skimmer for this size tank and it pulls in a very high amount of air.

Many homes have enough CO2 concentration in the air to cause pH swings..this isn't such an odd thing. Opening a window, when the weather permits, tends to raise my tanks pH by .20 to .50. As for swings, I'm talking 7.6 at night and 7.8 during the day if I don't drip kalk 24x7. I use a pH meter that is calibrated once a month, probe was replaced about 3 months ago.

For comparison, my last house was built in 1950 and was drafty as mosquito netting and my pH rarely went below 8.0."]

That is odd... do you have a refuge with macros in it? And if so whats the lighting cycle you use?
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@Marc wrote:
Baked baking soda mixed in RO water will bring that pH up said:
Yep, I know it will and I use it often. I dose Randy's 2-part every day in addition to kalkwasser.
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@GraviT wrote:
[I]@DaveJ wrote:[/I][quote=" That is odd... do you have a refuge with macros in it? And if so whats the lighting cycle you use? said:
Yep, I run a refugium with chaetomorpha, lit 24x7."]

Well that swing is what I would expect with the fuge going... but the raw number that low is still odd unless your tank is eating ca/alk and mg at such a rate that it drops on you. When you get it up to 8.2 or above, how long does it stay up there?
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@DaveJ wrote:
Well that swing is what I would expect with the fuge going... but the raw number that low is still odd unless your tank is eating ca/alk and mg at such a rate that it drops on you. When you get it up to 8.2 or above said:
Without kalk, not very long.

I just tested and my parameters are a bit low, Ca is at 400 and Alk is just a hair above 9, but I haven't dosed my 2 part today. Adding my usual 3/4 cup of the Alk portion (baked baking soda and water) raised the pH from 7.8 to 8.0. This is also the amount needed to raise Alk to 11. I expect my pH to be a bit wacky right now though as I just finished day 1 of a 3 day blackout.
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@GraviT wrote:
[I]@DaveJ wrote:[/I][quote=" Well that swing is what I would expect with the fuge going... but the raw number that low is still odd unless your tank is eating ca/alk and mg at such a rate that it drops on you. When you get it up to 8.2 or above said:
Without kalk, not very long.

I just tested and my parameters are a bit low, Ca is at 400 and Alk is just a hair above 9, but I haven't dosed my 2 part today. Adding my usual 3/4 cup of the Alk portion (baked baking soda and water) raised the pH from 7.8 to 8.0. This is also the amount needed to raise Alk to 11. I expect my pH to be a bit wacky right now though as I just finished day 1 of a 3 day blackout."]

Which receipt are you using? 1 or 2?

http://www.twopartsolution.com/index.php?main_page=page_4&zenid=e3fe715d24938a24aeee1cb3f7decb1c


No wonder you had such a hard time keeping your pH up as part of the dino elimination project!
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I keep my Alk around 9 and my PH runs 7.5 (night) to (8.0 day). I also have a refugium that is lighted 24X7 and a skimmer that's rated for a much larger tank.

Oh and yes I have a calcium reactor... It runs 6.6 most of the time.
 
@DaveJ wrote:
Which receipt are you using? 1 or 2? [url=http://http://www.twopartsolution.com/index.php?main_page=page_4&zenid=e3fe715d24938a24aeee1cb3f7decb1c]http://www.twopartsolution.com/index.php?main_page=page_4&zenid=e3fe715d24938a24aeee1cb3f7decb1c[/url] No wonder you had such a hard time keeping your pH up as part of the dino elimination project! said:
I'm using Randy's recipe 1 with baked baking soda to raise pH. Yep, keeping my pH up is a pain in the......


Bill, I feel your pain!! :D
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@GraviT wrote:
[I]@DaveJ wrote:[/I][quote=" Which receipt are you using? 1 or 2? [url=http://http://www.twopartsolution.com/index.php?main_page=page_4&zenid=e3fe715d24938a24aeee1cb3f7decb1c]http://www.twopartsolution.com/index.php?main_page=page_4&zenid=e3fe715d24938a24aeee1cb3f7decb1c[/url] No wonder you had such a hard time keeping your pH up as part of the dino elimination project! said:
I'm using Randy's recipe 1 with baked baking soda to raise pH. Yep, keeping my pH up is a pain in the......


Bill, I feel your pain!! :D"]

Kevin,

I spoke with Andrew from 2 part today about another issue and was asking him about the recipes. One of the things he asked was about my current pH levels and he said that the 2nd one (using baking soda) would lower the pH a bit, not raise it.

If you taking a look at the link, it the difference is the two components that make up the alk portion. The first uses Soda Ash and the other Baking soda.

Or is baked Baking Soda the same as Soda Ash?
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