# Non-CO2 Tank: Air Pump Or Not?



## Raymond S. (Dec 29, 2012)

They say that an elephant is a mouse built to military specs. This question may be similar.
Filter used to be run by air pumps. A reasonable bio-load of fish can live in a tank without any air pump, but once you pass a certain level of bio-load it becomes necessary to add more oxygen via water circulation. An HOB filter does this fairly well. So will a properly adjusted outlet of a canister filter. Or just an air stone. The water will only hold a certain amount of Oxygen and it is not harmful to anything in your tank.
Depending on your filter, the water circulation may be taken care of already.
CO2 does not enter the water by direct contact/w the water at as fast of a rate that a fully planted tank will use it. But we're talking not being able to see the back of that tank for so many plants. But then that is why these tanks need added circulation.
I'd say the air pump is more of a choice to help circulation.
No harm in a non injected CO2 tank.
More Oxygen and CO2 if you do have one.


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## PlantedRich (Jul 21, 2010)

As Raymond points out, the air isa okay but then it may not be needed. When water is next to air, bad gas goes out and good air comes in until a natural state is reached. So if we have water moving around, up and down so that it all goes up and takes it's turn at the top, gas exchange happens. The air we always used to bubble in tanks took water from the bottom up to the top. A very slight amount was actually exchanged due to the bubbles contact with the water. The side of a bubble is a pretty small amount compared to the whole water surface? Think of the bubbles as a water mover more than actually putting air in the tank. Can't get too much air in as it will just leak out when the water reaches the top.


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## Teebo (Jul 15, 2015)

Thanks guys, I did not realize it was more for circulation. I can see how the surface exchanges oxygen its just not possible to cap a tank and inject CO2 that way I suppose lol.


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## Argus (May 22, 2013)

If your plants are pearling during the daytime it is probably overkill. However, you might want to run it at night. Plants use oxygen and release CO2 during the night (lights off). They do this 24 hrs. per day to convert sugars into energy (just like other life forms), but photosynthesis typically produces more oxygen than the plant uses when there is sufficient light. So, during the day there is a net production of oxygen.


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## BBradbury (Nov 8, 2010)

*No CO2*

Hello tee...

Simple answer. Oxygen is a plant byproduct. The plants work to remove it, so adding an air stone that mixes more O2 into the water isn't good for your plants. If your filter system has a gph (gallons per hour) rating of at least 4 times the volume of your tank, then this is enough to aerate the water, you don't need to add another piece of equipment to the tank. This is just more labor for nothing in return.

Keep things simple in the "water keeping" hobby and you'll be successful.

B


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## Oso Polar (Apr 22, 2015)

BBradbury said:


> Simple answer. Oxygen is a plant byproduct. The plants work to remove it, so adding an air stone that mixes more O2 into the water isn't good for your plants.


Simple answer. And wrong. Plants not only produce oxygen, they also consume it. They certainly don't mind higher amount of oxygen, after all, plants can happily grow in the atmosphere that contains about 21% of oxygen - in the water you'll never ever come to anything close because solubility of oxygen in the water is low.


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## Steve001 (Feb 26, 2011)

Teebo said:


> I have some low tech tanks with no CO2 systems, I have been using an air pump thinking it is better than nothing since the are traces of CO2 in the air obviously and plants thrive off some of it, so I use a diffuser for fine bubbles. Plants give off oxygen so can too much build up? Someone told me get rid of the air pump and diffuser completely what do you think? Run it on a timer with the lights?


In a low tech tank using an airpump isn't a good idea because you are driving out co2 if the diffuser produces big bubbles which rise quickly to the surface. However, if this diffuser produces *very fine bubbles that do remain in contact with the water for a long time then it may be useful for keeping a stable level of co2. It depends also how large the water volume is and total contact time. Use a water pump to move water. It will also aid in keeping those fine bubbles in the water column longer so the ambient co2 gas can diffuse more completely.
* Examples https://www.youtube.com/watch?v=7-o2f1ULnMo
https://www.youtube.com/watch?v=tr6NdxmZCJk


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## Audionut (Apr 24, 2015)

Henry's law states that the concentration of gas (CO2) in water will always try and reach equilibrium with the atmosphere.



> An everyday example of Henry's law is given by a carbonated soft drink in a bottle. Before it is opened, the gas above the drink is almost pure carbon dioxide at a pressure higher than atmospheric pressure. The drink itself contains dissolved carbon dioxide. When the bottle is opened, this gas escapes, giving the characteristic hiss. Because the partial pressure of carbon dioxide above the liquid is now much lower, some of the dissolved carbon dioxide comes out of the solution as bubbles. If the drink is left in the open, the concentration of carbon dioxide in solution will come into equilibrium with the carbon dioxide in the air, and the drink will go "flat".


In a low tech tank without external CO2 injection, the plants are able to consume CO2 at a faster rate then the gas can maintain equilibrium (with atmosphere). We all know this as the pH swings during day and night periods.

So at some point during the light period of a low tech tank (somewhat dependent on bioload I guess), the plants will have consumed enough CO2 in the water to lower the concentration below that of the surrounding atmosphere. Here, increased surface agitation will help to maintain CO2 at equilibrium with the atmosphere.

As always in life, the answer is usually, "It depends".


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## Teebo (Jul 15, 2015)

Steve001 said:


> However, if this diffuser produces *very fine bubbles that do remain in contact with the water for a long time then it may be useful for keeping a stable level of co2. It depends also how large the water volume is and total contact time. Use a water pump to move water. It will also aid in keeping those fine bubbles in the water column longer so the ambient co2 gas can diffuse more completely.


I am using a CO2 diffuser on the air pump so they are extremely fine and float around the tank without pearling. Getting any CO2 from the atmosphere into my water is the goal here. My bubbles are as small as the ones in your video using a glass CO2 diffuser:












Audionut said:


> Henry's law states that the concentration of gas (CO2) in water will always try and reach equilibrium with the atmosphere.
> 
> In a low tech tank without external CO2 injection, the plants are able to consume CO2 at a faster rate then the gas can maintain equilibrium (with atmosphere). We all know this as the pH swings during day and night periods.
> 
> So at some point during the light period of a low tech tank (somewhat dependent on bioload I guess), the plants will have consumed enough CO2 in the water to lower the concentration below that of the surrounding atmosphere. Here, increased surface agitation will help to maintain CO2 at equilibrium with the atmosphere.


Ok so if this theory is correct, it makes sense to me! It reaches equilibrium with not only Oxygen but CO2 and any other gas(es) in our atmosphere I would assume so I can see how surface agitation would help with equilibrium. These are only 10 gallon tanks with a HOB so they get more air exchange than a canister filter. The air pump is loud and annoying so if you guys think I can really remove it I will, also I have no fish in these tanks I just use Osmocote root tabs.


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## Audionut (Apr 24, 2015)

Monitor pH. If pH is higher at the end of the photoperiod compared to the beginning of the photoperiod, CO2 has been consumed.



Steve001 said:


> In a low tech tank using an airpump isn't a good idea because you are driving out co2 if the diffuser produces big bubbles which rise quickly to the surface. However, if this diffuser produces *very fine bubbles that do remain in contact with the water for a long time then it may be useful for keeping a stable level of co2.


Smaller bubbles have increased surface area, so larger bubbles will drive out CO2 at a reduced rate to smaller bubbles. The longer a bubble remains in water, the longer (period of time) gas exchange can occur, so external bubbles added to the aquarium which have a lower concentration of CO2 then in the water, and hence can drive off CO2, will do so at an increased rate.

I'm not entirely sure what your trying to point out here, but it sounds exactly opposite to what actually happens.


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## Teebo (Jul 15, 2015)

I dont think I ever factored in the CO2 being high before the lights come on in the morning, and the tank being higher in CO2 concentration than the atmosphere in the morning.


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## BBradbury (Nov 8, 2010)

Hello oso...

Thanks for the information. I disagree with it, but this is your privilege. Plants take in CO2 from the air surrounding the tank and from the fish when they exhale. Plants give off O2 for the benefit of the fish. If you use an air stone to mix more O2 into the water, CO2 is forced out of the water, so there's less for the plants. A high O2 environment isn't the best for a planted tank. So, to avoid adding more O2 in a planted tank, you simply rely on the filter system to do the job of aerating the tank, this is what it does best.

Thanks again,

B


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## Steve001 (Feb 26, 2011)

Audionut said:


> Monitor pH. If pH is higher at the end of the photoperiod compared to the beginning of the photoperiod, CO2 has been consumed.
> 
> 
> 
> ...


The molecules in very small bubbles have time to diffuse out. I believe in my first video link it shows this taking place. The bubbles seem to disappear. For the same reason large co2 bubbles aren't used to put co2 into the water, little dwell time. Larger bubbles spend less or no appreciable time dwelling in the water column.


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## Argus (May 22, 2013)

BBradbury said:


> Hello oso...
> 
> Thanks for the information. I disagree with it, but this is your privilege. Plants take in CO2 from the air surrounding the tank and from the fish when they exhale. Plants give off O2 for the benefit of the fish. If you use an air stone to mix more O2 into the water, CO2 is forced out of the water, so there's less for the plants. A high O2 environment isn't the best for a planted tank. So, to avoid adding more O2 in a planted tank, you simply rely on the filter system to do the job of aerating the tank, this is what it does best.
> 
> ...


I don't understand this notion that an air bubbler is going to drive out CO2. Is there some documentation for it somewhere? I couldn't find any. 

An air pump and air stone or glass diffuser setup is not pumping pure oxygen. It is adding atmospheric air which contains both O2 and CO2. Essentially, it is doing nothing more than increasing the agitation of the water and the surface area exposed to the atmosphere. Most sources I've found say that CO2 in a planted tank can be replenished by exposure to the atmosphere. 

Plants use oxygen and give off CO2 while converting sugars to energy. This respiration happens 24/7 and occurs in most life forms.

Plants only give off O2 during photosynthesis. At night there is insufficient light to drive photosynthesis. Fast growing plants produce more O2 during daylight hours than they consume in 24 hrs. So, they are net producers of O2 and consumers of CO2. However, in a heavily planted tank, with a good bio-load of bacteria and fish, there could be periods where O2 drops to very low levels. This would also depend on the ratio of the water's surface area to volume. A deep tank might need the added surface exposure that a bubbler adds.

Bump:


Steve001 said:


> The molecules in very small bubbles have time to diffuse out. I believe in my first video link it shows this taking place. The bubbles seem to disappear. For the same reason large co2 bubbles aren't used to put co2 into the water, little dwell time. Larger bubbles spend less or no appreciable time dwelling in the water column.


Large bubbles can be used if their dwell time is increased with a Hagen ladder or similar device.










Notice how the bubbles get smaller at the top and almost vanish.


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## Audionut (Apr 24, 2015)

Steve001 said:


> For the same reason large co2 bubbles aren't used to put co2 into the water, little dwell time. Larger bubbles spend less or no appreciable time dwelling in the water column.


So they won't drive out CO2 faster either then?



Steve001 said:


> In a low tech tank using an airpump isn't a good idea because you are driving out co2 if the diffuser produces big bubbles which rise quickly to the surface.


Or is there some unique property where larger bubbles can remove CO2 better then they can diffuse CO2?


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## Steve001 (Feb 26, 2011)

Audionut said:


> So they won't drive out CO2 faster either then?


 You can see in both vids how easily those tiny bubbles are moved about by the water pumps. 



Or is there some unique property where larger bubbles can remove CO2 better then they can diffuse CO2?[/QUOTE]
Big bubbles create an upwelling of water to the surface liberating any dissolved gases into the atmosphere in contrast to waterpumps which would moved water around the tank limiting the aforementioned liberation.


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## Audionut (Apr 24, 2015)

Steve001 said:


> Big bubbles create an upwelling of water to the surface liberating any dissolved gases into the atmosphere in contrast to waterpumps which would moved water around the tank limiting the aforementioned liberation.


I think you'll find that *any* bubbles reaching the surface, _whether big or small_, will increase the surface area of the water, leading to faster equilibrium of the gases. So I'm not sure how the comparison to a water pump, that has it's outflow positioned so as not to increase surface agitation, and hence, surface area, is related to this discussion.

http://www.digipac.ca/chemical/mtom/contents/chapter3/chap3_6.htm


> Increasing the surface area in a heterogeneous reaction will normally increase the reaction rate. It does so because with more surface area exposed between the two reacting states, there will be more collisions and therefore a greater chance for a reaction.


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## Teebo (Jul 15, 2015)

Argus said:


> An air pump and air stone or glass diffuser setup is not pumping pure oxygen. It is adding atmospheric air which contains both O2 and CO2. Essentially, it is doing nothing more than increasing the agitation of the water and the surface area exposed to the atmosphere. Most sources I've found say that CO2 in a planted tank can be replenished by exposure to the atmosphere.


This is exactly what is driving me to post this thread roud: in this case if CO2 builds up at night, I should run the air pump on a timer during the end of my light cycle only.


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## Argus (May 22, 2013)

Teebo said:


> This is exactly what is driving me to post this thread roud: in this case if CO2 builds up at night, I should run the air pump on a timer during the end of my light cycle only.


Possibly. It depend on whether their is already enough surface area and agitation to equalize CO2 and O2 levels with the atmosphere. Maybe it would be needed and maybe it would not. Unfortunately, there don't seem to be any tests that an aquarist can use to get a clear picture of O2 and CO2 levels. 

However, I don't see the harm in running a air pump and bubbler at night.

Edit: In rereading I see an error. It is not that CO2 builds up at night. The problem is that O2 can be depleted. So, the danger is oxygen starvation, not CO2 poisoning.


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## Steve001 (Feb 26, 2011)

Argus said:


> I don't understand this notion that an air bubbler is going to drive out CO2. Is there some documentation for it somewhere? I couldn't find any.
> 
> An air pump and air stone or glass diffuser setup is not pumping pure oxygen. It is adding atmospheric air which contains both O2 and CO2. Essentially, it is doing nothing more than increasing the agitation of the water and the surface area exposed to the atmosphere. Most sources I've found say that CO2 in a planted tank can be replenished by exposure to the atmosphere.
> 
> ...


This photo illustrates what I've been saying; bubbles will get smaller if the gas within has time to diffuse out.

Bump:


Teebo said:


> This is exactly what is driving me to post this thread roud: in this case if CO2 builds up at night, I should run the air pump on a timer during the end of my light cycle only.


That doesn't make much sense. If you bubble all night or a portion of it then you drive out any co2 for the start of the next day. Have you looked into what Diana Walstad has to say on this subject? She has oddles of experience with low tech tanks.


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## Steve001 (Feb 26, 2011)

Audionut said:


> I think you'll find that *any* bubbles reaching the surface, _whether big or small_, will increase the surface area of the water, leading to faster equilibrium of the gases. So I'm not sure how the comparison to a water pump, that has it's outflow positioned so as not to increase surface agitation, and hence, surface area, is related to this discussion.
> 
> Changing Equilibrium: Surface Area


you haven't been paying attention closely. A typical bubbler creates an upwell of water to the surface. There is practically no mixing at the water/atmosphere interface and little exchange of atmosphere with tank water. Here's a vid demonstrating what I just wrote. https://www.youtube.com/watch?v=ihlFp8d1jn0
see what I mean?
One uses a waterpump to circulate and keep those gases, namely co2 in the tank a long as possible. Btw, if one were to point a waterpump upward the affect would be the same as a bubbler.


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## Argus (May 22, 2013)

Steve001 said:


> That doesn't make much sense. If you bubble all night or a portion of it then you drive out any co2 for the start of the next day. Have you looked into what Diana Walstad has to say on this subject? She has oddles of experience with low tech tanks.


I'm having trouble understanding this idea that agitation and exposure to the air (what bubbling does) will drive out all CO2.

The air contains CO2.
Plants that have leaves above water have better access to CO2. 
Henry's law says that gasses dissolved in water will try to reach equilibrium with those in the air. 

I've looked in *Ecology of the Planted Aquarium* by Diana Walstad. On page 73 she talks about oxygen depletion during the night and looks for signs of labored breathing in fish. She says she uses, "...only the amount of aeration that is necessary. For excessive areation can remove all CO2 from the water..." However, she doesn't explain how this works. So, I still don't understand how aeriation can deplete all CO2.


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## Daisy Mae (Jun 21, 2015)

Maybe these numbers can put certain things into perspective. 

Atmospheric air is composed of
78% Nitrogen
21% Oxygen
*0.039%* Carbon Dioxide

Henry's law will tend to drive the concentration of CO2 in tank water to equilibrate with the 0.039% CO2 concentration in the atmosphere.


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## Teebo (Jul 15, 2015)

Steve001 said:


> That doesn't make much sense. If you bubble all night or a portion of it then you drive out any co2 for the start of the next day. Have you looked into what Diana Walstad has to say on this subject? She has oddles of experience with low tech tanks.


Exactly thats why I said at the end of the LIGHT period not all night or during the dark period at all only after its all used up at the end of the day before it needs oxygen at night.


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## Audionut (Apr 24, 2015)

Argus said:


> I'm having trouble understanding this idea that agitation and exposure to the air (what bubbling does) will drive out all CO2.


It doesn't drive out all the CO2. _It *increases* the *surface area* of the water, which *speeds up equilibrium*_.

If there is more of a gas in the water then in the atmosphere, the gas will want to escape the water to reach equilibrium with the atmosphere.

If there is more of a gas in the atmosphere then in the water, the gas will want to enter the water to maintain equilibrium with the atmosphere.

An air bubbler does this through two actions. Both are a result of increased surface area. Lets deal with the easy one first. 

Take a balloon (full of air, but only to give it size), and immerse this balloon under water. Now allow the balloon to break the waters surface. Surface tension of water means that the balloon doesn't exit the water in a dry state. Instead, the elasticity of water means that there will be a film of water over the balloon.

So in some aquarium, we have some amount of water, with some amount of surface area. If we just sit this balloon half way into the water, and imagine that it is covered in aquarium water, do you see the increased surface area of the water? Now imagine a bunch of constantly escaping bubbles of air. Surface tension works here too.


The second method of increased surface area that may or may not be harder to understand.

In an aquarium, it's surface area to the atmosphere is simply the length times the width of the waters surface. If we take a bubble of atmosphere and insert it into the water, what do you think happens to the surface area? Not only do we simply have the surface area of the surface water, but we also now have the surface area of the bubble itself, since the bubble contains atmosphere, and this bubble is in contact with the water.

This is how CO2 injection with a diffuser works. Bubbles of CO2 are injected _into_ the water. Henry's law applies, which means the higher concentration of CO2 in the bubble wants to maintain equilibrium with the water itself, and hence the CO2 dissolves into the water.

We know that smaller bubbles diffuse the CO2 into the water better then larger bubbles, because if we take a number of smaller bubbles that would fit into a larger bubble, the number of smaller bubbles represent a larger surface area. I haven't found an easy description of this that doesn't involve complex maths, but anyone with any interest in science should be able to understand this relationship to surface area. I have no idea what Steve is trying to describe, but I hold the laws of physics and the laws of chemistry in higher regard then youtube videos.

Once the bubble exits the water into the atmosphere, Henry's law stops because the bubble is no longer in contact with the water. So here, smaller bubbles generally work better because they are easier to maintain in contact with the water (they have less buoyancy), which simply means that the time the bubble is in contact with the water is greater, and hence Henry's law can apply for a longer period of time. 

Henry's law works both ways. If you have an aquarium with a large amount of dissolved CO2, and inserted a bubble of atmosphere (with less CO2) into the water, and could maintain this bubble in the water, the bubble would increase in size as equilibrium happens between the water and the bubble.



Daisy Mae said:


> Henry's law will tend to drive the concentration of CO2 in tank water to equilibrate with the 0.039% CO2 concentration in the atmosphere.


It's partial pressure.

https://en.wikipedia.org/wiki/Partial_pressure
https://en.wikipedia.org/wiki/Carbonic_acid#pH_and_composition_of_carbonic_acid_solutions


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## Daisy Mae (Jun 21, 2015)

Right, my bad for using concentration. 
0.3 mm Hg of CO2 in 760 mm Hg of various atmospheric gases at sea level
which amounts to 0.000394 of CO2 per 1 atmosphere


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## burr740 (Feb 19, 2014)

A low tech tank operates with CO2 roughly in the 3ppm range. Surface agitation will greatly help maintain this baseline level. The more the better actually.

Most tanks with CO2 injection are operating in the 20-30+ range. Under these conditions surface agitation causes CO2 to off-gas faster. That isnt necessarily a bad thing because you get the added benefit of increased O2. Most people just crank it more to compensate for the loss. CO2 is cheap.


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## essabee (Oct 7, 2006)

The only way you can drive all oxygen and carbon dioxide from water (which is exposed to atmosphere) is by keeping it at boiling temperature. CO2 will not drive out O2 and vice versa. The gasses contained by any body of water will always tend to have an equilibrium position (for the temperature of the water) with the composition of atmospheric air it is in contact with. If this contact atmospheric air is replaced with a composition of air rich in CO2 (or O2) then the equilibrium position in the water will be rich in CO2 (or O2 as the case may be).

This equilibrium position gets warped by respiration and also by photosynthesis of the flora and fauna when the rate of diffusion to and from the atmospheric air cannot keep pace with the byproducts (CO2 & O2). So in case of our planted fish tanks the CO2 levels tend to be higher than equilibrium levels during non-photosynthesis period and the O2 levels tends to get higher than equilibrium levels sometime after the photosynthesis period has started and the CO2 level starts to drop during this period. This happens because the diffusion from and to the atmospheric air is limited - especially by the contact surface area and the slow physical rate at which natural diffusion takes place.

Aeration by air pumps creates water flow and increases contact area of water and atmospheric air. It does not either drive out CO2 / O2 or add them; what it does actually is change the rate rate of natural diffusion upwards by increasing the air contact area and flow caused by it tends to homogenise the water body.

The size of the bubbles for the same volume of gas has a direct relation to the surface area and creation of flow. Taking the flow created by bubble size (assuming volume of the gas *supply* a constant) first --- Large bubbles have a greater force of buoyancy and will accelerate upwards faster but then will be fewer in numbers of bubbles. With gradual reduction in size of bubbles we tend to see greater number of bubbles and slower upward acceleration and a greater spread in area these bubbles occupy. With very fine bubbles we find that their upward movement appears to be laboured and their numbers astronomical and they tend to move haphazardly like a cloud. The flow rate of the moving water column created by these bubbles tends initially to increase with the gradual dimmunisation of bubble size then to remain constant and then the flow starts to slacken. It should also be noted here that as the flow slackens the numbers of bubbles - the volume of the gas in the combined number of bubbles present in the water column at any given moment increases although the gas *supply* is/remains a constant - this is because the dwell period of the bubbles in the water column has increased.

The surface area: A sphere has the smallest surface in relation to its volume and a gas bubble in water tend to assume the shape of a sphere and therefore present the minimum surface area. The ratio of the surface area of a sphere to its volume decreases with the size of the sphere. So as the bubbles increase in numbers the sum total of their combined surface area tends to increase. We may tend to lose the flow rate with very fine bubbles but we gain higher surface areas.

When we introduce CO2 gas using fine bubbles or reactors what we are actually doing is forming an air-surface contact with an atmosphere of nearly pure CO2. This changes the equilibrium ratio of the gasses in the tank to one which is richer in CO2.


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## roadmaster (Nov 5, 2009)

Teebo said:


> This is exactly what is driving me to post this thread roud: in this case if CO2 builds up at night, I should run the air pump on a timer during the end of my light cycle only.


 Yes if you want to run air pump ,it would be of better benefit at night when plant's are using up oxygen.
But in moderately to heavily planted tank's, and healthy plant mass,the plant's produce enough oxygen during the day to provide for the fishes at night so long as you are not grossly overstocked.
In low tech NON CO2 tank's ,the CO2 build up at night would be of little concern to me for it ain't that much.


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## Steve001 (Feb 26, 2011)

Audionut said:


> It doesn't drive out all the CO2. _It *increases* the *surface area* of the water, which *speeds up equilibrium*_.
> 
> If there is more of a gas in the water then in the atmosphere, the gas will want to escape the water to reach equilibrium with the atmosphere.
> 
> ...


Audionut has explained it much better than I have.


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## Teebo (Jul 15, 2015)

That explains a lot thank you, so in summary bubbles do both circulation and absorption; "air" is for circulation and it takes concentrated CO2 to be able to be absorbed. I understood the surface area of bubbles with finer air stones/diffusers which is why I was lead to believe I could get some CO2 from "air" if I used a diffuser on an air pump.


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## Teebo (Jul 15, 2015)

*I am back on this subject again, I have a riparium with a very heavy plant load. I am having problems with Nerite snails dying on me, and Mystery Apple snails siphoning oxygen at the water surface. I believe they are lacking oxygen although my shrimp seem fine. Since plants consume O2 when the lights are off I think they are over-consuming it leaving the water stripped of O2. I added an air pump on a timer to run at night, combined with a glass diffuser to make it more effective. It has helped a little but not making its impact yet, since I am not injecting this tank with CO2 gas (I use Excel) so I do not have to worry about off-gassing with an air pump right? I say this because I feel the need to run it 24/7 until I get to the bottom of my Nerite issues.*


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