Tried all I can to fix pH

[Rauland]

So I am having trouble with Ph in my 125 gallon mixed reef. Up to now I dosed via pumps C-Balance and have a hang-on skimmer connected to CO2 scrubber. I have 2 HOB Refugiums with Cheato. I also dose vinegar 28 mls/day. My measured phosphate via Hanna is 0 and nitrate 0. I also tried placing airline outside with no change. Last 2 day I am dosing Kalk in my ATO water mixed at 2 tsp per gallon. Probably add about 1 gallon per day and dosing midnight to 9 am every hour. You can see my ph probe graph below and I do have 2 probes that agree. On the 3rd day shown I dosed washing soda hoping that raising ph that would be help keep it high. You can also see 2 spikes the last couple morning that I added a larger dose of kalk water but is short lived and drops back down. This morning I'm down to 7.6. Not sure what else to do.

I had a similar issue with my 93 cube sps dominate tank. I tried everything and finally hired someone from my lfs to come service my tank. Turns out the deep sand bed was the problem. Just one thing to consider. Good luck.

 

[Bonfish]

I have been working to resolve a similar issue. Sump was installed in the basement with the display on the first floor. I have done all that has been recommended thus far as well. If I shut my windows pH drives down. I was looking into purchasing an air exchanger for my HVAC. I have not decided on which is best but I was thinking a renew air ERV. Good luck and if this works for me I will let you know.

 

[Randy Holmes-Farley Verified Community Expert]

I had a similar issue with my 93 cube sps dominate tank. I tried everything and finally hired someone from my lfs to come service my tank. Turns out the deep sand bed was the problem. Just one thing to consider. Good luck.

Deep sand bed was causing low pH?

 

[badhabits]

I would check your CO2 scrubber media and look into the light you put on your refugium,more photosynthesis =more oxygen=more ph if all else fails you can look into dosing 8.4

 

[Randy Holmes-Farley Verified Community Expert]

I would check your CO2 scrubber media and look into the light you put on your refugium,more photosynthesis =more oxygen=more ph if all else fails you can look into dosing 8.4

Just a minor correction, it's not the O2 that matters for pH, but CO2. They do not always track together.

more photosynthesis =less CO2 = higher pH.

 

[badhabits]

Just a minor correction, it's not the O2 that matters for pH, but CO2. They do not always track together.

more photosynthesis =less CO2 = higher pH.

I must respectfully both agree and disagree if that makes any sense.There is a direct correlation between dissolved oxygen and PH in sea water. Almost everything you can do to increase O2 will decrease CO2 as they are always struggling to reach equilibrium

 

[Velcro]

I have been using AquaVitro Balance to raise Ph. It doesn't affect Alk at all and works great for when the air conditioning is on for days straight. Running an air hose outside isn't enough. After a week of closed windows and doors, I had a Ph of 7.8. It took hours for the Ph to rise to 8.1 with every window and door open. My 93 cube is also right next to my screen door and it still took that long.

Check out Balance.

It is not possible to raise pH without affecting alkalinity with any chemical assuming there is some amount of CO2 in the tank. Aquavitro balance is just potassium hydroxide and sodium hydroxide... if there is CO2 in the tank then the hydroxide from the KOH and NaOH WILL raise the alkalinity. It's the same as dosing kalk.

 

[Velcro]

I must respectfully both agree and disagree if that makes any sense.There is a direct correlation between dissolved oxygen and PH in sea water. Almost everything you can do to increase O2 will decrease CO2 as they are always struggling to reach equilibrium

I thought dissolved gasses act independently of each other?

 

[badhabits]

They do but because of hydrogens affinity for ionic bonding it will more readily exchange electrons with oxygen over carbon and almost any other element.PH is just a measurement of the molar concentration of that ion IMO chasing that 8.3 "ideal PH" just causes more stability issues than it is worth

 

[Randy Holmes-Farley Verified Community Expert]

I must respectfully both agree and disagree if that makes any sense.There is a direct correlation between dissolved oxygen and PH in sea water. Almost everything you can do to increase O2 will decrease CO2 as they are always struggling to reach equilibrium

I disagree. Many things we do impact only one or the other. They do not always move together in reef tanks, and one is definitely not predictive of the other.

1. Adding high pH alkalinity additives such as limewater/kalkwasser or sodium carbonate consume (reduce) CO2 and have no impact on O2. My tank using limewater ran pH 8.35 to 8.55 all the time, whether O2 was high or low (day vs night) whereas many others have much lower pH (and hence more CO2) but not necessarily any less O2.

2. Folks using CaCO3/CO2 reactors directly add CO2 without adding O2. That is why their tanks often run low in pH.

3. Folks using carbon denitrators produce some CO2 without consuming a proportional amount of O2 because the O for the CO2 is coming from nitrate.

4. Folks dosing hydrogen peroxide or ozone are adding O2, and not consuming CO2. In fact, they may be generating CO2 as well.

 

[Randy Holmes-Farley Verified Community Expert]

I thought dissolved gasses act independently of each other?

They do.

It is true that many processes that impact one impact the other, but in a reef tank one can (and does) often have both elevated, both low, or one high and the other low.

There is little correlation in reef tanks overall.

 

[Randy Holmes-Farley Verified Community Expert]

1, Both O2 and CO2 high:

Case: reef tanks during the day in a home with elevated CO2 levels. The pH often does not hit 8.2, but the O2 may well be saturated or higher at its peak.

2, Both O2 and CO2 low

My reef tank at night, with limewater dosing the pH is well above 8.2 even at night, but the O2 is likely not saturated (so is "low").

3. O2 high and CO2 low

case: many reef tanks at peak during the day. High pH and high O2.

4. O2 low and CO2 high

case: many reef tanks at night where O2 drops and CO2 rises,

 

[Randy Holmes-Farley Verified Community Expert]

It is not possible to raise pH without affecting alkalinity with any chemical assuming there is some amount of CO2 in the tank. Aquavitro balance is just potassium hydroxide and sodium hydroxide... if there is CO2 in the tank then the hydroxide from the KOH and NaOH WILL raise the alkalinity. It's the same as dosing kalk.

Quite right. It adds alkalinity same as limewater/kalkwasser.

I don't know if their misleading advertising is intentionally wrong or just reflecting ignorance, but it is nonsense nonetheless.

http://www.aquavitro.com/products/balance.html

"raises pH without affecting calcium and alkalinity"

TOTAL CRAPOLA!

 

[Forsaken77]

Quite right. It adds alkalinity same as limewater/kalkwasser.

I don't know if their misleading advertising is intentionally wrong or just reflecting ignorance, but it is nonsense nonetheless.

http://www.aquavitro.com/products/balance.html

"raises pH without affecting calcium and alkalinity"

TOTAL CRAPOLA!

How is it impossible to only raise Ph without affecting Alk? I mean I would take your word over some company that's looking to make money, but Seachem's premium Aquavitro line is pretty good stuff and comes from a reputable company. Don't you think they would have tested whether or not it affects Alk before making that claim on their product?

I went to one of the better LFS's in my area, of which there are about 10, and asked the owner if there was a product to raise Ph, but not Alk. He immediately showed me Balance. And like you stated, it says right on the bottle that it doesn't affect Alk or Calcium. Kind of like that API Ph Up product for freshwater, I thought.

Just curious how they R&D these products and why they would intentionally mislead people, and possibly ruin their rep, by making a claim if it wasn't backed up in their testing.

 

[Randy Holmes-Farley Verified Community Expert]

How is it impossible to only raise Ph without affecting Alk? I mean I would take your word over some company that's looking to make money, but Seachem's premium Aquavitro line is pretty good stuff and comes from a reputable company. Don't you think they would have tested whether or not it affects Alk before making that claim on their product?

I went to one of the better LFS's in my area, of which there are about 10, and asked the owner if there was a product to raise Ph, but not Alk. He immediately showed me Balance. And like you stated, it says right on the bottle that it doesn't affect Alk or Calcium. Kind of like that API Ph Up product for freshwater, I thought.

Just curious how they R&D these products and why they would intentionally mislead people, and possibly ruin their rep, by making a claim if it wasn't backed up in their testing.

There are lots of claims by manufacturers that either reflect ignorance, simple mistakes, or intentional misleading of customers. I have convinced several to change claims, but I have not contacted every one. Some I have fought tooth and nail in forums. Such issues are a big part of why I started Reef Chemistry forums years ago.

In this case, it is a no brainer. You do not need to test to understand that chemically, it is impossible to boost pH without boosting alkalinity. There are a number of ways to show it, but here's the simplest:

If you raise pH (that is, reduce H+) , you shift the equilibrium of carbonate and bicarbonate to the right due to Le Chatlier's Principle (making more carbonate from bicarbonate):

HCO3- <---> H+ + CO3--

Since CO3-- counts as two units of alkalinity, and HCO3- as only one, that shift increases alkalinity.

An alternative way of looking at it is to understand that the equation for what contributes to total alkalinity is:

TA = [HCO3-] + 2[CO3--] + [B(OH)4-] + [OH-] + [Si(OH)3O-] + [MgOH+] + [HPO4--] + 2[PO4---] - [H+]

As you can see, OH- is in that calculation so any addition of OH- boosts total alkalinity.

 

[Forsaken77]

There are lots of claims by manufacturers that either reflect ignorance, simple mistakes, or intentional misleading of customers. I have convinced several to change claims, but I have not contacted every one. Some I have fought tooth and nail in forums. Such issues are a big part of why I started Reef Chemistry forums years ago.

In this case, it is a no brainer. You do not need to test to understand that chemically, it is impossible to boost pH without boosting alkalinity. There are a number of ways to show it, but here's the simplest:

If you raise pH (that is, reduce H+) , you shift the equilibrium of carbonate and bicarbonate to the right due to Le Chatlier's Principle (making more carbonate from bicarbonate):

HCO3- <---> H+ + CO3--

Since CO3-- counts as two units of alkalinity, and HCO3- as only one, that shift increases alkalinity.

An alternative way of looking at it is to understand that the equation for what contributes to total alkalinity is:

TA = [HCO3-] + 2[CO3--] + [B(OH)4-] + [OH-] + [Si(OH)3O-] + [MgOH+] + [HPO4--] + 2[PO4---] - [H+]

As you can see, OH- is in that calculation so any addition of OH- boosts total alkalinity.

Gotcha. I'm not a chemistry/biologist, more of a tech guy. So when a LFS and a reputable company both make the same claim, I have no choice but to take their word on it. Chemistry just flies over my head.

 

[Randy Holmes-Farley Verified Community Expert]

. So when a LFS and a reputable company both make the same claim, I have no choice but to take their word on it. .

Or check in forums like this one.

 

[rob safron]

So an update on my pH issue. I ran skimmer line outside which really did not make much difference. I checked and replace my CO2 media every 5 days or so, probably sooner than I need. We happen to get a really nice evening so I opened the basement windows and that did the trick. Ph went from a low of 7.55 in the morning to a low of 7.78 24 hours later. I guess Refugium, CO2 media and Kalk were just not enough. Not sure that's solved the 100 degree days issue but I have an answer.

 

[SaltEverywhere]

How old is your tank? I have a 150 gallon that ran 7.7-7.9 when it was new no matter what I did. I was dosing baked baking soda because at least it was something. Over the coarse of a year and a half my pH slowly rose and now runs 8.1-8.3, so I switched back to regular baking soda with no change in pH ranges. I am guessing that as a tank matures the buffering system that keep the tank at normal sea water levels slowly develops? I will defer to the accumulated brain trust present on this forum, but it seems like once you have beat yourself to death doing all the usual things it may be that in the end a new tank will take time to settle in at 8.2. As long as you've tried everything and the current pH rang isn't hurting anything, you may be able to relax and let time solve it.

 

[Forsaken77]

Also I've noticed having the glass top on the tank will reduce gas off and lower Ph. I have to leave the glass doors on top open so more water is exposed to the air. If I close it up, with just the little gap in the back, the Ph plummets.

I swear I never had algae or Ph issues until I started using an RODI. Sounds crazy, I know. But I think the RODI lowered the Ph of my tap and now it's a constant issue. When the screen door next to the tank is open I get 8.1. When everything is shut I get 7.8 in the day and 7.7 at night.

I used to use crushed coral in my substrate back in the day. Think I'm going to mix some in so I don't have to worry about it anymore. Works much better than aragonite.