Co2 and Ph

[JoeQ]

How much affect is there with low levels of co2 and ph? Do guys running Low levels of co2 have to be constantly aware of drastic ph fluctuations? 

[Mmiller2001]

Low levels of CO2 has low affect on pH. PH swing from CO2 has no negative effect on fish. 

[MattyM]

I don't shoot for the max CO2 levels, but in case you haven't seen this, this is how I learned to know how much CO2 is in my tank at any given time (a digital ph meter is much better than a drop checker, once you know your numbers): 

CO2 levels in lakes and rivers change all the time throughout the day, fish are used to swings. I just try to keep it consistent. 

[JoeQ]

What about kh levels?  I'm assuming this is the mechanism that swings the ph. Is this assumption correct?

[Mmiller2001]

On 9/25/2022 at 7:10 AM, JoeQ said:

What about kh levels?  I'm assuming this is the mechanism that swings the ph. Is this assumption correct?

No, carbonic acid is formed from the injection of CO2. This is one acid responsible for lowering pH. KH is the buffering capacity of the water.

[JoeQ]

On 9/25/2022 at 9:21 AM, Mmiller2001 said:

No, carbonic acid is formed from the injection of CO2. This is one acid responsible for lowering pH. KH is the buffering capacity of the water.

Ok, thanks! I'm not too good with any of this sciencey stuff, but atleast want a rudimentary understanding of what is going on. 

[AnimalNerd98]

Another thing to be aware of is having the CO2 on a timer rather than always having the CO2 cranked. It should preferably come on about 1-2 hours before the lights come on and 1 hour before the lights go out. Times given by @Irene in the new Co-Op video on setting up CO2. 

Here is the Co-Op guide on pH, GH, and KH that may be helpful: https://www.aquariumcoop.com/blogs/aquarium/ph-gh-kh

Edited September 25, 2022 by AnimalNerd98

[JoeQ]

On 9/25/2022 at 1:22 PM, AnimalNerd98 said:

Another thing to be aware of is having the CO2 on a timer rather than always having the CO2 cranked. It should preferably come on about 1-2 hours before the lights come on and 1 hour before the lights go out. Times given by @Irene in the new Co-Op video on setting up CO2. 

Here is the Co-Op guide on pH, GH, and KH that may be helpful: https://www.aquariumcoop.com/blogs/aquarium/ph-gh-kh

Thanks , im aware of most of the nuances of co2, ive been researching it for a few years now  debating on  if it was worth the start up price to "tinker"  The only thing I did not research was its affects on water chemistry and the mechanics behind it.

Which I understand simply as this:

Kh, carbonate hardness, is, in essence a shield, and protects ph from substances in the water lowering said ph.

Carbonic acid doesn't necessarily affect ph, rather the ph self adjusts to reach a homeostasis with the carbonic acid.

[AnimalNerd98]

Here is the best way I can explain it (refer to diagram). I have colored the positive hydrogen ions (protons) red and the carbonate/carbon dioxide constituents blue for simplicity so you can track down the protons. 

When CO2 is dissolved in water, it can form carbonic acid (H2CO3). Carbonic acid can break down Into a single, positive hydrogen ion (a proton) as well as a bicarbonate ion. The bicarbonate ion can be further broken down into yet another proton and a carbonate ion. All of these molecules exist in a dynamic equilibrium (fluctuating ever so slightly depending on the relative concentrations of each molecule). 

When we talk about pH, we are talking about the power/potential of hydrogen. In other words, how many protons are present in the mixture? So, the more protons are available in the water, the more acidic the solution is and the lower the pH. 

Consider Scenario 1 in the diagram. If we are continuously pumping in CO2 and dissolving it into the water, we will have a relatively high concentration of CO2. This will shift the equilibrium further to the right (notice the bigger arrows pointing to the right), resulting in more and more hydrogen ions being produced and released into the water. This is what causes the pH to "drop."

However, the equilibrium can also shift in the opposite direction with the right circumstances. Let's say you dissolve baking soda (sodium BICARBONATE) in pure water and add it to an acidic solution with a low pH like vinegar. The equilibrium will shift to the left and CO2 bubbles will start gassing off as more bicarbonate ions join with protons to form carbonic acid, before becoming CO2 and water. 

Thus, we see how carbonate and bicarbonate ions act as buffers to prevent large changes in pH by acting as a reservoir/sink for hydrogen ions. When the pH is high, bicarbonate ions can form carbonate and a proton to make the solution more acidic and counteract the high pH. When the pH is low, carbonate ions can join up with free protons to form bicarbonate ions, making the solution less acidic and counter the low pH.

pH swings happen when there is not enough bicarbonate and carbonate ions to buffer against drastic changes in the amount of protons in the water. Look back at Scenario 1 in the image: if there are not enough carbonate ions to take up the free protons to form bicarbonate, more and more protons will enter the water making the water more and more acidic. 

Let me know if that explanation makes sense. 

Edited September 26, 2022 by AnimalNerd98

[JoeQ]

On 9/26/2022 at 3:01 AM, AnimalNerd98 said:

Here is the best way I can explain it (refer to diagram). I have colored the positive hydrogen ions (protons) red and the carbonate/carbon dioxide constituents blue for simplicity so you can track down the protons. 

When CO2 is dissolved in water, it can form carbonic acid (H2CO3). Carbonic acid can break down Into a single, positive hydrogen ion (a proton) as well as a bicarbonate ion. The bicarbonate ion can be further broken down into yet another proton and a carbonate ion. All of these molecules exist in a dynamic equilibrium (fluctuating ever so slightly depending on the relative concentrations of each molecule). 

When we talk about pH, we are talking about the power/potential of hydrogen. In other words, how many protons are present in the mixture? So, the more protons are available in the water, the more acidic the solution is and the lower the pH. 

Consider Scenario 1 in the diagram. If we are continuously pumping in CO2 and dissolving it into the water, we will have a relatively high concentration of CO2. This will shift the equilibrium further to the right (notice the bigger arrows pointing to the right), resulting in more and more hydrogen ions being produced and released into the water. This is what causes the pH to "drop."

However, the equilibrium can also shift in the opposite direction with the right circumstances. Let's say you dissolve baking soda (sodium BICARBONATE) in pure water and add it to an acidic solution with a low pH like vinegar. The equilibrium will shift to the left and CO2 bubbles will start gassing off as more bicarbonate ions join with protons to form carbonic acid, before becoming CO2 and water. 

Thus, we see how carbonate and bicarbonate ions act as buffers to prevent large changes in pH by acting as a reservoir/sink for hydrogen ions. When the pH is high, bicarbonate ions can form carbonate and a proton to make the solution more acidic and counteract the high pH. When the pH is low, carbonate ions can join up with free protons to form bicarbonate ions, making the solution less acidic and counter the low pH.

pH swings happen when there is not enough bicarbonate and carbonate ions to buffer against drastic changes in the amount of protons in the water. Look back at Scenario 1 in the image: if there are not enough carbonate ions to take up the free protons to form bicarbonate, more and more protons will enter the water making the water more and more acidic. 

Let me know if that explanation makes sense. 

Thanks, but no it does not make much sence. Im lost when it comes to ions, protons, neutrons and periodic table notation.  I best understand when It gets explained like you would explain it to a 2 year old with simple analogies and flashy pictures!  🤣

[PerceptivePesce]

@JoeQmakes the best threads! (for me to hijack! 😍 😁)

I'm trying to understand kH & pH like Joe. Let me try asking some Qs, maybe that will help us both gain insight.

Here's what I think I understand so far. Correct me if I'm wrong, please!

pH is an abbreviation of "power of hydrogen". When a pH reading is taken it is measuring the H+ in a solution. When a solution has more H+ it is acidic, when a solution has more H- it is basic.

So my question is, when CO2 is introduced into aquarium water is it rearranging the kH carbonate compounds? In lay terms could you say it (CO2) is "eating" the kH?

Edited September 26, 2022 by PerceptivePesce

[JoeQ]

On 9/26/2022 at 10:53 AM, PerceptivePesce said:

@JoeQmakes the best threads! (for me to hijack! 😍 😁)

I'm trying to understand kH & pH like Joe. Let me try asking some Qs, maybe that will help us both gain insight.

Here's what I think I understand so far. Correct me if I'm wrong, please!

pH is an abbreviation of "power of hydrogen". When a pH reading is taken it is measuring the H+ in a solution. When a solution has more H+ it is acidic, when a solution has more H- it is basic.

So my question is, when CO2 is introduced into aquarium water is it rearranging the kH carbonate compounds? In lay terms could you say it is "eating" the kH?

Hijack away! Often times I get more from reading than by posting. I'll reclaim my thread when it's appropriate!  😂

[AnimalNerd98]

On 9/26/2022 at 6:25 AM, JoeQ said:

Thanks, but no it does not make much sence. Im lost when it comes to ions, protons, neutrons and periodic table notation.  I best understand when It gets explained like you would explain it to a 2 year old with simple analogies and flashy pictures!  🤣

Sorry about that! I will try to amend it to make it more beginner-friendly. Most of it is understanding and memorizing the terms itself.

Ions are just atoms or molecules with a positive or negative charge. Thus, an H+ ion is just a hydrogen atom that lost an electron, making it positively charged and just a proton. Because pH is the power/potential of hydrogen, we want to track how many free hydrogen ions are in the water. If the protons are bound to anything else like bicarbonate, it doesn't count. More protons = lower pH and acidic, less protons means higher pH and basic. 

But maybe this terminology is intimidating. Let's call protons/H+ ions (same thing) smiley faces. Carbonate is blue pac man. Bicarbonate is just a blue pac man fused to a yellow smiley face. 

How does this analogy work for you?

[AnimalNerd98]

On 9/26/2022 at 8:53 AM, PerceptivePesce said:

@JoeQmakes the best threads! (for me to hijack! 😍 😁)

I'm trying to understand kH & pH like Joe. Let me try asking some Qs, maybe that will help us both gain insight.

Here's what I think I understand so far. Correct me if I'm wrong, please!

pH is an abbreviation of "power of hydrogen". When a pH reading is taken it is measuring the H+ in a solution. When a solution has more H+ it is acidic, when a solution has more H- it is basic.

So my question is, when CO2 is introduced into aquarium water is it rearranging the kH carbonate compounds? In lay terms could you say it (CO2) is "eating" the kH?

1) Yes, pH is an abbreviation of the power of hydrogen

2) A solution is more acidic when a solution has more H+, and more basic when it has less H+. H- is another hydrogen ion, but it is not the ion that we measure for pH. Sorry for the confusion. But technically, if a solution has a lot of H-, it will be more basic but this reasoning requires a more intense chemical explanation. 

3) When CO2 is added to the water, it makes the water more and more acidic. So in a way, yes, it is "eating up" the carbonate compounds in the aquarium.

Edited September 26, 2022 by AnimalNerd98

[JoeQ]

On 9/26/2022 at 12:49 PM, AnimalNerd98 said:

Sorry about that! I will try to amend it to make it more beginner-friendly. Most of it is understanding and memorizing the terms itself.

Ions are just atoms or molecules with a positive or negative charge. Thus, an H+ ion is just a hydrogen atom that lost an electron, making it positively charged and just a proton. Because pH is the power/potential of hydrogen, we want to track how many free hydrogen ions are in the water. If the protons are bound to anything else like bicarbonate, it doesn't count. More protons = lower pH and acidic, less protons means higher pH and basic. 

But maybe this terminology is intimidating. Let's call protons/H+ ions (same thing) smiley faces. Carbonate is blue pac man. Bicarbonate is just a blue pac man fused to a yellow smiley face. 

How does this analogy work for you?

Even worse! I've never seen a proton much less a positive or negatively charged one, so that holds no meaning. Now if you drew a bunch of baby pac-mans (the number of pac-mans corresponding with bps) attacking a bubble labled ph, surrounded by another bubbled labeled kh..... Id totally get that!!!! 😂

Edited September 26, 2022 by JoeQ

[AnimalNerd98]

On 9/26/2022 at 12:01 PM, JoeQ said:

Even worse! I've never seen a proton much less a positive or negatively charged one, so that holds no meaning.  🤣 Now if you drew a bunch of baby pac-mans (the number of pac-mans corresponding with bps) attacking a bubble labled ph, surrounded by another bubbled labeled kh..... Id totally get that!!!! 😂

I’m sorry, I’m trying my best 😂 Maybe someone has an alternative explanation that works better. By the way, what is bps? 
 

 

Edited September 26, 2022 by AnimalNerd98

[JoeQ]

Bps = bubble per second or bass pro shop depending on the forum im on!

[AnimalNerd98]

Ahh, I see what you mean now for the analogy. So carbon dioxide makes carbonic acid in water. The acid can lower aquarium pH, but the components that make up KH are preventing the acid from lowering the pH too much. Once the shield of KH has been broken down, pH will be “attacked” by the acid making it swing down.

Something like this? 

[JoeQ]

On 9/26/2022 at 2:11 PM, AnimalNerd98 said:

Ahh, I see what you mean now for the analogy. So carbon dioxide makes carbonic acid in water. The acid can lower aquarium pH, but the components that make up KH are preventing the acid from lowering the pH too much. Once the shield of KH has been broken down, pH will be “attacked” by the acid making it swing down.

Something like this? 

Something like that but your fancy negative and positive protons probably play a roll since the ph swings regardless of kh (i believe) the degree of kh (thickness) might dictate how big of a swing the ph goes thru. 

[PerceptivePesce]

Y'all are cute 🥰

@AnimalNerd98

So, is CO2 wasted in high kH solutions? Does low kH water retain more CO2?

[AnimalNerd98]

On 9/26/2022 at 6:46 PM, PerceptivePesce said:

Y'all are cute 🥰

@AnimalNerd98

So, is CO2 wasted in high kH solutions? Does low kH water retain more CO2?

I wouldn't say it is wasted in high KH because the dissolved CO2 is what the plants use anyways for photosynthesis. As long as the CO2 is not reaching its saturation point, CO2 will continue to dissolve into the water which is available for the plants to take up (before it is all converted into carbonic acid).

Bicarbonate and carbonate interact with the product of CO2 reacting with water, not necessarily with carbon dioxide itself. If anything, I think temperature has a bigger factor in determining how much CO2 is held in the water. For example, cold water has a greater solubility for gases like carbon dioxide and oxygen. This is the reason why it is more important to add air stones to tanks with high temps because the solubility of oxygen for fish is relatively low in comparison to cooler tanks. 

Edited September 27, 2022 by AnimalNerd98

[AnimalNerd98]

On 9/26/2022 at 12:17 PM, JoeQ said:

Something like that but your fancy negative and positive protons probably play a roll since the ph swings regardless of kh (i believe) the degree of kh (thickness) might dictate how big of a swing the ph goes thru. 

True! KH is not an invulnerable shield but it can temper the blows of otherwise larger pH swings.

Edited September 27, 2022 by AnimalNerd98

[JoeQ]

On 9/26/2022 at 8:46 PM, PerceptivePesce said:

Y'all are cute 🥰

 

I would classify myself as more adorable than cute!  😁

[PerceptivePesce]

I'm out of questions. Maybe I'll come up with some after I digest this thread a bit. 

Somewhat related. I stumbled into a reddit thread where the big brains were hypothesizing about archaea being the beneficial organism in low pH tanks. They were saying something like bacteria can't live in lower pH, the bad kind nor the beneficial kind, and that archaea were responsible for doing the nitrogen cycle conversion stuff.  Something like that, I def could be recalling wrong.  Twas interesting tho

[Minanora]

On 9/25/2022 at 6:21 AM, Mmiller2001 said:

No, carbonic acid is formed from the injection of CO2. This is one acid responsible for lowering pH. KH is the buffering capacity of the water.

I'm on my phone so I can't remove the quote.... But @AnimalNerd98 & @Mmiller2001

Does the carbonic acid and CO2 precipitate and break down into carbonate and bicarbonate? Do they actually raise pH?

While the CO2 is off, pH is higher. Without regular water changes can the pH get even higher due to CO2 injection?

I change water regularly on my injected tank and my water is liquid rock so it's hard to see what's going on long term.

Does the carbon go free and need to bind to something? What happens to it....

Chemical reaction.... And dissolution...

🤔