Alkalinity and pH

[Val Shebeko]

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Hey all !

Right now I’m holding at about 8 pH and alk is about 9.9 dKH using a fair amount of sodium hydroxide.
LFS in Elgin is recommending Tropic Marin saying it really supports alk. What happens to my pH when alk goes up and I can’t use as much sodium hydroxide ?

 

[Randy Holmes-Farley]

What exactly do you mean by recommending Tropic Marin? They sell many products.

That said, not are suitable for you to use to boost pH.

 

[Val Shebeko]

What exactly do you mean by recommending Tropic Marin? They sell many products.

That said, not are suitable for you to use to boost pH.

They like TM as a salt and apparently among its many virtues it lifts alkalinity .

Since I am doding Sodium Hydroxide to boost pH and Sodium Hydroxide also boosts alkalinity
I am wondering if it TM will boost pH or it will impair my ability to dose Sodium Hydroxide to maintain my pH.

Currently using Reef Crystals and with the Sodium Hydroxide I am maintaining a pH of 8 ~ and this morning alk was at 9.9 dKH.

I’m running a CO2 scrubber, which scrubs outside air before giving it to the skimmer.

Indoor CO2 is at 712 ppm. The Sodium Hydroxide is at 4 tablespoons per gallon of RODI.

 

[Peer.Boerner]

They like TM as a salt and apparently among its many virtues it lifts alkalinity .

Since I am doding Sodium Hydroxide to boost pH and Sodium Hydroxide also boosts alkalinity
I am wondering if it TM will boost pH or it will impair my ability to dose Sodium Hydroxide to maintain my pH.

Currently using Reef Crystals and with the Sodium Hydroxide I am maintaining a pH of 8 ~ and this morning alk was at 9.9 dKH.

I’m running a CO2 scrubber, which scrubs outside air before giving it to the skimmer.

Indoor CO2 is at 712 ppm. The Sodium Hydroxide is at 4 tablespoons per gallon of RODI.

Do you mean Calcium Hydroxide (Kalkwasser)? Sodium Hydroxide is lye which you’d need in very low quantities compared to Kalkwasser.

 

[Val Shebeko]

Do you mean Calcium Hydroxide (Kalkwasser)? Sodium Hydroxide is lye which you’d need in very low quantities compared to Kalkwasser.

Lye. Dosing a solution of about 700 mils over 24 hours. 4 tablespoons of food grade in a gallon. 225 gallon system.

 

[Randy Holmes-Farley]

The LFS is misguided. There are higher alk mixes, but Tropic Marin is not among them, and in any case, if you use the sodium hydroxide to raise the alk you will get a higher pH than starting with a high alk mix.

 

[Bear22]

I am looking for a salt that mixes low in alkalinity, but high (ish) in pH. Is such a thing even possible?

Assuming my CO2 monitor is somewhere in the ball park in terms of accuracy it's measuring 420ppm as I type this. Yet, I am having low pH issues.

 

[Val Shebeko]

The LFS is misguided. There are higher alk mixes, but Tropic Marin is not among them, and in any case, if you use the sodium hydroxide to raise the alk you will get a higher pH than starting with a high alk mix.

I’m not smart enough to explain myself coherently. That’s my problem.

I am wondering if the TM, will interfere with my ability to dose Sodium Hydroxide at current levels, i.e about 700 mils / 24 hours by boosting the the alkalinity and apparently doing nothing to increase or at least maintain the current level of pH which is about 8. As alkalinity rises I will be forced to cut back on SH and face a drop of pH.

Or am I better off staying with Reef Crystals and the Sodium Hydroxide? It seems I’m getting plenty of alkalinity boost off of the Sodium Hydroxide at current concentration of 4 tablespoons per gallon.

 

[Val Shebeko]

I am looking for a salt that mixes low in alkalinity, but high (ish) in pH. Is such a thing even possible?

Assuming my CO2 monitor is somewhere in the ball park in terms of accuracy it's measuring 420ppm as I type this. Yet, I am having low pH issues.

You and me both

 

[Sisterlimonpot]

I’m not smart enough to explain myself coherently. That’s my problem.

I am wondering if the TM, will interfere with my ability to dose Sodium Hydroxide at current levels, i.e about 700 mils / 24 hours by boosting the the alkalinity and apparently doing nothing to increase or at least maintain the current level of pH which is about 8. As alkalinity rises I will be forced to cut back on SH and face a drop of pH.

Or am I better off staying with Reef Crystals and the Sodium Hydroxide? It seems I’m getting plenty of alkalinity boost off of the Sodium Hydroxide at current concentration of 4 tablespoons per gallon.

I know this isn't answering your question, but I think what is throwing a lot of us back is the use of sodium hydroxide vs calcium hydroxide.

Not to say reefers don't dose sodium hydroxide but not without understanding the risks and having a sound plan to make it work. I may be wrong, but it sounds like you were given the advice to dose sodium hydroxide for a potent pH boost, but that also throws off your calcium carbonate balance.

The downside to sodium hydroxide is that you raise alkalinity without calcium. You would need to supplement calcium to keep the balance.

What is being suggested without saying it directly is that this approach may not be your best option. As there are better ways to increase pH as well as maintain CaC03 balance.

Unfortunately, there's no magic bullet that will allow you to raise your pH without affecting other parameters, especially alkalinity. Well, there are C02 absorbing media that can help remove C02 before your skimmer pulls in air. That has mixed results. I'm sure there are others, but with very little bang for your buck.

 

[Val Shebeko]

Dosing calcium and mg. Not alot but a bit. The calcium hydroxide results were underwhelming more or less. So I don’t know what the other options really are. Guess I’m staying with Reef Crystal since it’s the devil I know. Appreciate your time, your patience, and your good humor. Thank you.

 

[Randy Holmes-Farley]

I am looking for a salt that mixes low in alkalinity, but high (ish) in pH. Is such a thing even possible?

Assuming my CO2 monitor is somewhere in the ball park in terms of accuracy it's measuring 420ppm as I type this. Yet, I am having low pH issues.

Not really. Alk determines pH if you aerate it on mixing.

 

[Bear22]

Not really. Alk determines pH if you aerate it on mixing.

Randy when you say "aerate it on mixing"; can you expound on this?

 

[Randy Holmes-Farley]

Randy when you say "aerate it on mixing"; can you expound on this?

When you dissolve a salt mix you stir it, that also aerates it to add oxygen and when you do that, CO2 equilibrates with the air, pegging the pH by the alk and CO2 level.

You really cannot have a high pH salt mix that is stable. It will both suck in CO2, lowering pH, and may begin to precipitate calcium carbonate if you keep CO2 out (which also lowers pH).

 

[Bear22]

When you dissolve a salt mix you stir it, that also aerates it to add oxygen and when you do that, CO2 equilibrates with the air, pegging the pH by the alk and CO2 level.

You really cannot have a high pH salt mix that is stable. It will both suck in CO2, lowering pH, and may begin to precipitate calcium carbonate if you keep CO2 out (which also lowers pH).

Hmmm,

I use a powerjet to mix my salt every single time. No pegging of the pH is happening.

 

[Randy Holmes-Farley]

Hmmm,

I use a powerjet to mix my salt every single time. No pegging of the pH is happening.

What do you mean? What do you observe for pH in the new salt water?