Rising alkalinity after pegging pH at 8.3

[Nerdist Aquarist]

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.

 

[mdb_talon]

Well you are dosing more alk than being consumed in an effort to get the ph boosting effect...so likely it will just keep rising because you keep dosing more than is consumed. I guess there is a chance growth picks up because of the stable ph and higher alk...it consumes more alk...and balances out. I think that would be unlikely at least to the degree needed.

 

[Dennis Cartier]

Well you will reach an equilibrium where more alk will not be required to sustain the pH you have targeted. This will occur as the alk required to maintain a dKH of n will provide enough boost to the pH to not require an increase in alk. Also the higher the alk level, the more alk it requires to maintain that level. So an equilibrium is definitely coming, but hard to say what level it will be at.

The wildcard is your corals and their growth. They may take some time to acclimate to the higher alk and pH, and either speed up or slow down their growth as they go through that acclimation. Once you are on the backside of the hill, so to speak, and your corals are increasing their growth rate (if the benefit you are trying to achieve rings true), than the alk level should start to drop and your pH should start to rise, requiring you to back off your dosing to keep the pH within your target, or at least that is the theory of the style of dosing management you are attempting to follow.

Good luck and watch your corals for signs of distress. Do report back how this works for you.

Dennis

 

[Garf]

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.

Got a pic of your tank?

 

[Nerdist Aquarist]

Appreciate all the great feedback so far! Here are a couple pics for you Garf

 

[Garf]

Appreciate all the great feedback so far! Here are a couple pics for you Garf

Very nice. I tend to agree about pH. . Hope all goes well for you.

 

[GARRIGA]

Brightwell Akalin 8.3 claims it keeps raising alkalinity once PH pegged at 8.3. Used twice just to see how much alkalinity rose with PH so can’t comment beyond that. Perhaps others can chime in. Apparently doesn’t just use soda ash.

 

[ClownSchool]

I was under the impression adding sodium hydroxide raised ph, but lowered alkalinity. So, am I understanding it right that you’re adding sodium hydroxide while boosting your dose of higher alkaline as well?
if that’s the case, wouldn’t it be a more stable adjustment to add soda ash and keep your alkaline dose the same?
Or, am I confusing sodium hydroxide and soda ash?

 

[Garf]

I was under the impression adding sodium hydroxide raised ph, but lowered alkalinity. So, am I understanding it right that you’re adding sodium hydroxide while boosting your dose of higher alkaline as well?
if that’s the case, wouldn’t it be a more stable adjustment to add soda ash and keep your alkaline dose the same?
Or, am I confusing sodium hydroxide and soda ash?

Hydroxides increase alkalinity.

 

[Nerdist Aquarist]

Yes, hydroxides increase alkalinity as well. It combines with CO2 in the water therefore creating the carbonate that way. Soda ash was my previous additive, but doesn't give the same level of pH boost.

 

[Garf]

Yes, hydroxides increase alkalinity as well. It combines with CO2 in the water therefore creating the carbonate that way. Soda ash was my previous additive, but doesn't give the same level of pH boost.

Personally I think Alk swings have been blamed for causing problems, when they are actually the result of another problem which results in low uptake. Not all, obviously. pH is a good candidate.

 

[arking_mark]

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.

Pretty reckless experiment for chasing pH stability in my opinion.

You're basically using a high pH Alkalinity supplement to "peg" pH and hoping both pH and Alk will stabilize.

The only way they stabilize is if you're Alk consumption meets your dosing.

Higher pH does increase Alk/Ca consumption through increased abiotic and biological CaCO3 production. So its's possible that it stabilizes, but it's literally a shot in the dark.

This would never work for an immature tank with low Alk/Ca consumption.

Additionally, since pH swings with your house CO2 which can vary widely throughout the day depending on number of CO2 sources (people, pets, cooking, open windows, etc...) . You will find your dosing swinging to meet it.

At the end of the day you will probably find you have stable pH and unstable Alk.

If your Alk goes too high, you'll end up with a precipitation event.

Of note, is that higher Alk also means higher pH.

Let's say a well aerated tank averages 8.1 pH and 8dKH and ignore photosynthesis. We can calculate CO2 levels...650ppm.

If we increase Alk to 12, we can calculate the pH with the same CO2 levels...8.25.

This is why many reefers run their tanks at higher Alk as it provides a higher pH.

If you want both pH and Alk stability, I suggest you try something else.

Lessons learned in trying to maintain pH stability

For those interested in maintaining pH stability around +/- 0.05 I have a couple of lessons learned. These are things that I found out on my journey to pH stability. Prior to seeking pH stability my tank pH was consistently around ~7.9. However, much of this journey went on before the tank was...

www.reef2reef.com

 

[ClownSchool]

Yes, hydroxides increase alkalinity as well. It combines with CO2 in the water therefore creating the carbonate that way. Soda ash was my previous additive, but doesn't give the same level of pH boost.

I used soda ash for the first time, yesterday. I usually limit it to a two-part dosing, but I noticed my ph had dropped to 8.0. So, last night, when ph is supposed to be going down, it was still at 8.3, but this morning it has dropped to 8.0 again.
One of my torches is retracted, but other than that, everything else looks fine.
Should I be worried?

 

[arking_mark]

I used soda ash for the first time, yesterday. I usually limit it to a two-part dosing, but I noticed my ph had dropped to 8.0. So, last night, when ph is supposed to be going down, it was still at 8.3, but this morning it has dropped to 8.0 again.
One of my torches is retracted, but other than that, everything else looks fine.
Should I be worried?

Possibly. You should only use Alk additives for Alk dosing. Adding Alk based on pH could spike your alkalinity. Alk swings are often culprits of coral issues...

 

[arking_mark]

I used soda ash for the first time, yesterday. I usually limit it to a two-part dosing, but I noticed my ph had dropped to 8.0. So, last night, when ph is supposed to be going down, it was still at 8.3, but this morning it has dropped to 8.0 again.
One of my torches is retracted, but other than that, everything else looks fine.
Should I be worried?

The pH boost from high pH additives are temporary...

 

[Nerdist Aquarist]

My alkalinity reached 12 today while pegging an 8.3 pH. So I've decided to peg 8.2 as the low point for now and see how that goes. I'm sure as Alk demand increases over time with coral growth it may allow me to target a higher pH. At the end of the day, my goal was to peg a stable pH 24/7. So for now, aiming for 8.3 seems to be too high of a number. The beauty of it is I'm using custom programming with my apex, Trident and DOS. So it's just a matter of editing a single line. I can also enter a max limit for Alk to stop dosing all together until it falls back within range.

All corals still looking great.

 

[PeterEde]

My LFS put me onto Seachem Marine buffer. PH peaks at 8.3 and ALK will rise to where you want then figure out the daily amount to does to keep it there.

 

[Nerdist Aquarist]

My LFS put me onto Seachem Marine buffer. PH peaks at 8.3 and ALK will rise to where you want then figure out the daily amount to does to keep it there.

I may look into this in the future. One of the reasons I selected sodium hydroxide is the cost basis. I bought 6 bottles of sodium hydroxide for $40. I'm now 7 months using it and I just finished my second bottle. That beats high quality sodium bicarbonate or soda ash by miles.

 

[Miami Reef]

I do believe this was an “impulsive” experiment.

Adding a refugium, using ventilation from outside, adding a CO2 scrubber are just some ways of raising PH without risking a lot of money in dead corals.

I don’t mean to scare you, but many acros display a “delayed response” to many stressing events. It takes a few weeks for a coral to show the negative effects of a change that happened back.

If this was me, I would try to stabilize the tank and not do such reckless experiments anymore.

I mean this in a helpful and friendly way.

 

[Nerdist Aquarist]

I do believe this was an “impulsive” experiment.

Adding a refugium, using ventilation from outside, adding a CO2 scrubber are just some ways of raising PH without risking a lot of money in dead corals.

I don’t mean to scare you, but many acros display a “delayed response” to many stressing events. It takes a few weeks for a coral to show the negative effects of a change that happened back.

If this was me, I would try to stabilize the tank and not do such reckless experiments anymore.

I mean this in a helpful and friendly way.

I hear you, but I wouldn't say it's impulsive. I've done my planning plus all the other methods you mentioned. I do have precautions in place, as I mentioned 12 Alk was my cutoff. Been reefing for 12 years now, I get bored from time to time, lol.