Rising alkalinity after pegging pH at 8.3

[PeterEde]

Most tanks don't regulate pH and in-home CO2 levels will often vary regularly between 400 to 1000ppm CO2. With typical Alk this will fluctuate pH between 7.9 and 8.3 with photosynthesis and other things boosting it a little higher depending on your setup. Many of these tanks are beautiful and have no problem with coral.

I have a CO2 meter on the way. Just an excessive tool to annoy me probably

 

[arking_mark]

I have a CO2 meter on the way. Just an excessive tool to annoy me probably

It's really good for understanding your root cause for pH in your tank.

 

[markwayts]

There's been a lot of talk in recent months about the benefits of elevating pH, so like the daredevil I am I've elevated and stabilized my pH between 8.3-8.4 24/7 by dialing in my alkalinity dosing only at night. I use sodium hydroxide as my buffer so the pH effects is significant. Over the past 5 days my dkh has increased from 8.5 to 10.5, which is no surprise to me.

My question is to anyone whose attempted anything similar. Will alkalinity eventually stabilize and how long could it take? For now I'm totally comfortable, and I don't plan on backing off until dkh gets to 12. Corals are looking totally fine for now.

Yes, I've heard about not chasing numbers. At the very least I'm treating this as an experiment. I do believe a stable pH is more beneficial than stable dkh.

I do it a different way. I dose saturated calk solution to almost my evaporation limit for the alk and Ph boost. I make up the rest of the alk needs with all for reef. Keeps ph between 8.2 and 8.4 plus I get some trace elements.

 

[PeterEde]

I only got 30gl tank do I need to chase these numbers really

 

[Dennis Cartier]

I only got 30gl tank do I need to chase these numbers really

I would just shoot for stability. With a smaller tank, it is a lot easier for parameters to swing. So just trying to keep things stable and within the acceptable range would be what I would suggest. Once you get the hang of keeping your corals healthy and happy, then you can tweak for perfection.

Dennis

 

[Dennis Cartier]

It's an OK product (although of unknown purity). It's the claim about it pegging the aquarium at pH 8.3 that is incorrect.

It does not do that. The kernal of truth around that misleading claim is that when added to seawater, it tugs the pH toward 8.3 (whether that is up or down). It's just a mix of mostly bicarbonate and a little carbonate that does that.

But most people do not get as much pH boost as they want from it, and do not get a steady pH 8.3. They would be better off with a pure carbonate supplement, or best yet in terms of pH boost, hydroxide.

On their product page for it, they tout the inclusion (and reliance) of borate in it for it's ability to buffer to a higher pH. Do you not believe that they are using borate in it? Does elevating borate affect corals? Is there such a thing as too much borate and not enough bicarbonate?

I was just reading your article on the relationship between pH and Alkalinity and noticed that you included Seachem's strategy of elevating borate in their salt mixes to buffer at a higher pH. Ahem, that article is 20 years old this year!

Dennis

 

[Randy Holmes-Farley Verified Community Expert]

On their product page for it, they tout the inclusion (and reliance) of borate in it for it's ability to buffer to a higher pH. Do you not believe that they are using borate in it? Does elevating borate affect corals? Is there such a thing as too much borate and not enough bicarbonate?

I was just reading your article on the relationship between pH and Alkalinity and noticed that you included Seachem's strategy of elevating borate in their salt mixes to buffer at a higher pH. Ahem, that article is 20 years old this year!

Dennis

I believe they are using borate. It's not something I recommend. Seachem is big on borate and used to have 10x normal levels in their salt mix for pH stability. Fortunately they stopped that.

i do not think borate in a reef tank alk supplement is desirable. Corals consume carbonate and you add back borate and carbonate. Long term what happens? Seems to me borate rises. Of course, they may add so little it doesn't rise, but then what's the point aside from trying to make it look preferable to baking soda.

Borate does have a minor effect on pH stability, but it does not drive the pH toward any particular value.

I discuss those effects here:

Chemistry And The Aquarium: Boron In A Reef Tank

This article also discusses the sources and sinks for boron in reef tanks, and shows that while typical tanks may be slightly depleted in boron with respect to natural levels, most are not so significantly depleted that any correction is required. Nevertheless, how to test for and supplement...

reefs.com

 

[uninformed]

I did not make the claim, others did.

Now I never once said anything said by others is or is not the truth! I was letting to op know of a possible reason for the issue they are observing, giving them something to research, as a possible cause for the effect. In the end, it's 2 different hydroxide, so I assume that info won't help either way

Everyone would do themselves a big favor if they stopped listening to Chris from ACI. Every time I hear him speak about chemistry, I cringe. He is exactly what is meant by "just enough knowledge to be dangerous." He is entertaining and may know how to run a successful business, but he clearly lacks a fundamental understanding of chemistry—or at the least the ability to speak about it in a coherent way. The confusing way that he approaches this subject leads people down the wrong paths and creates even more confusion about how to control pH and alkalinity. This entire thread is evidence of that.

Keep listening to @Randy Holmes-Farley and stay away from the ACI guy. Please.

Source: I am a chemical engineer with many years of experience in industrial water treatment.

 

[PigFarmer]

Thank you for leaving well enough alone and for the will to be a brave soul to take this plunge and document it for all us skeerdy cats! Nothing in stasis is new or exciting. I Look forward to seeing how this pans out. Once again... Thanks man!

 

[Ashish Patel]

Everyone would do themselves a big favor if they stopped listening to Chris from ACI. Every time I hear him speak about chemistry, I cringe. He is exactly what is meant by "just enough knowledge to be dangerous." He is entertaining and may know how to run a successful business, but he clearly lacks a fundamental understanding of chemistry—or at the least the ability to speak about it in a coherent way. The confusing way that he approaches this subject leads people down the wrong paths and creates even more confusion about how to control pH and alkalinity. This entire thread is evidence of that.

Keep listening to @Randy Holmes-Farley and stay away from the ACI guy. Please.

Source: I am a chemical engineer with many years of experience in industrial water treatment.

You are right, but this is true for a lot of ppl in the hobby. 10-15 years ago it was chasing near 0 nutrients (failed), then it became dosing Nitrates (failed), now it its chasing PH (will fail for more hobbyist that not).

 

[Shooter6]

Everyone would do themselves a big favor if they stopped listening to Chris from ACI. Every time I hear him speak about chemistry, I cringe. He is exactly what is meant by "just enough knowledge to be dangerous." He is entertaining and may know how to run a successful business, but he clearly lacks a fundamental understanding of chemistry—or at the least the ability to speak about it in a coherent way. The confusing way that he approaches this subject leads people down the wrong paths and creates even more confusion about how to control pH and alkalinity. This entire thread is evidence of that.

Keep listening to @Randy Holmes-Farley and stay away from the ACI guy. Please.

Source: I am a chemical engineer with many years of experience in industrial water treatment.

I do a kalkwasser, magnesium, and all for reef combination that keeps my parameters stable on my 700g system.

I was only trying to help the op out with solving his questions.

 

[uninformed]

I do a kalkwasser, magnesium, and all for reef combination that keeps my parameters stable on my 700g system.

I was only trying to help the op out with solving his questions.

I apologize if that came across as a dig at you; it definitely wasn't.

 

[Shooter6]

I apologize if that came across as a dig at you; it definitely wasn't.

I understand. The potassium hydroxide is interesting to me as ill be adding another 5-600gal to this system soon and could probably benefit from implementing it, although I'd definitely do a ton more research on it first. Unfortunately there's not much info out as of now.

 

[Randy Holmes-Farley Verified Community Expert]

I understand. The potassium hydroxide is interesting to me as ill be adding another 5-600gal to this system soon and could probably benefit from implementing it, although I'd definitely do a ton more research on it first. Unfortunately there's not much info out as of now.

It's certainly reasonable to pursue hydroxide and or potassium, but I see little reason to tie them together. That part makes no sense to me since the two reason to dose them are entirely unrelated to each other.

Hydroxide is a nice alk additive with the highest possible pH boost. It is in long use in kalkwasser and more recently, in my two DIY two part Recipes using it for the alk part (as sodium hydroxide).

I've heard of some folks boosting potassium to unnaturally high levels for some effect (coloration, I think). Not sure how useful that is or how/why it works. I have recommended potassium chloride for potassium dosing. it is cheap and easy to obtain.

 

[Shooter6]

It's certainly reasonable to pursue hydroxide and or potassium, but I see little reason to tie them together. That part makes no sense to me since the two reason to dose them are entirely unrelated to each other.

Hydroxide is a nice alk additive with the highest possible pH boost. It is in long use in kalkwasser and more recently, in my two DIY two part Recipes using it for the alk part (as sodium hydroxide).

I've heard of some folks boosting potassium to unnaturally high levels for some effect (coloration, I think). Not sure how useful that is or how/why it works. I have recommended potassium chloride for potassium dosing. it is cheap and easy to obtain.

I dose potassium regularly to keep it within the green on my icp test. I personally found an increase in growth as well as color when potassium was raised to the upper levels of the green range.

If dosing as small amount as has been claimed, maintains alk on large systems, and additionally adds enough potassium to maintain it as well, then I can see it as a great option.

I've never used it myself though so I cannot make a definitive statement on it.
I started with kalkwasser in the late 80s. Moved to a calcium reactor, 3 part dosing, all for reef, and now came back almost full circle to a kalkwasser/all for reef combo.
If potassium hydroxide is as potent as has been claimed I could definitely see it being used in place or alongside kalkwasser, since it could help those who's demand out runs kalkwasser dosing capacity.

I guess we will have to wait for someone to actually test it and post their findings.

 

[Nerdist Aquarist]

Here's an update on my results so far doing this experiment.

For the last 2 days I've backed off the sodium hydroxide dosing a bit, pegging my pH to not go below 8.2 at night (I stop dosing when my lights ramp up to peak intensity) and photosynthesis naturally takes the pH up to 8.3 later in the day. Alkalinity levels is now on the decrease, about 10.2 now. I'll give it a couple more days then see about pegging 8.25 pH at the low.

Most corals seem to be the same, except for the Bubblegum Digi, and Battle Coral Magic Wand which visibly appear more "bushy" with better poly extension. On the negative side, my Duncan has retracted some.

 

[Shooter6]

It's certainly reasonable to pursue hydroxide and or potassium, but I see little reason to tie them together. That part makes no sense to me since the two reason to dose them are entirely unrelated to each other.

Hydroxide is a nice alk additive with the highest possible pH boost. It is in long use in kalkwasser and more recently, in my two DIY two part Recipes using it for the alk part (as sodium hydroxide).

I've heard of some folks boosting potassium to unnaturally high levels for some effect (coloration, I think). Not sure how useful that is or how/why it works. I have recommended potassium chloride for potassium dosing. it is cheap and easy to obtain.

45 lb Pail Potassium Hydroxide Meets Food Chemical Codex High Grade Red Hot Devil Caustic Potash Flakes 45 lb Pail Potassium Hydroxide Meets Food Chemical Codex High Grade Red Hot Devil Caustic Potash Flakes Seems to be readily available too..
I found liquid food grade as well as scientific grade? Online in stock and ready to ship. So I don't think the ease to obtain would be an issue. Hopefully someone who can run an actual experiment with it will and post their findings.

 

[Randy Holmes-Farley Verified Community Expert]

I dose potassium regularly to keep it within the green on my icp test. I personally found an increase in growth as well as color when potassium was raised to the upper levels of the green range.

If dosing as small amount as has been claimed, maintains alk on large systems, and additionally adds enough potassium to maintain it as well, then I can see it as a great option.

I've never used it myself though so I cannot make a definitive statement on it.
I started with kalkwasser in the late 80s. Moved to a calcium reactor, 3 part dosing, all for reef, and now came back almost full circle to a kalkwasser/all for reef combo.
If potassium hydroxide is as potent as has been claimed I could definitely see it being used in place or alongside kalkwasser, since it could help those who's demand out runs kalkwasser dosing capacity.

I guess we will have to wait for someone to actually test it and post their findings.

I just don't see it being sensible. There's zero reason to tie potassium dosing and alkalinity dosing together.

Adding 1.4 dKH (0.5 meq/L) of alk a day via potassium hydroxide will boost potassium by 28 ppm.

That's a massive potassium boost for a normal alk boost, and is why folks cannot use just KOH.

But why use any KOH at all? Why not just add whatever alk you want by whatever method (including sodium hydroxide, which is no more expensive and can be more potent than KOH, if that matters) and then use cheap food grade KCl for the exact potassium boost you want?

 

[Randy Holmes-Farley Verified Community Expert]

45 lb Pail Potassium Hydroxide Meets Food Chemical Codex High Grade Red Hot Devil Caustic Potash Flakes 45 lb Pail Potassium Hydroxide Meets Food Chemical Codex High Grade Red Hot Devil Caustic Potash Flakes Seems to be readily available too..
I found liquid food grade as well as scientific grade? Online in stock and ready to ship. So I don't think the ease to obtain would be an issue. Hopefully someone who can run an actual experiment with it will and post their findings.

If you want to use KOH (or NaOH or KCl), I'd use food grade.

 

[markwayts]

I do a kalkwasser, magnesium, and all for reef combination that keeps my parameters stable on my 700g system.

I was only trying to help the op out with solving his questions.

Me too. Same setup smaller tank. Works great. Brought my Ph up and accelerated my growth.