# How to set up your CO2 Controller and why they are so good!



## ray-the-pilot (May 14, 2008)

Enclosed is my recently published paper on CO2 controllers. Unfortunately it requires 3 separate Word documents and is rather technical; however, I did want you to understand how valuable these devices are.

If you only want to know how to set up your controller just open part 3 and go to the section titled: How to set up your controller?

These documents are copyright and unauthorized distribution of them is prohibited; however, you may quote any part as long as point to this site and give credit to ray-the-pilot.

I suggest sending any controversial comment to me as a PM.


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## Left C (Jun 14, 2005)

That is a very nice post.


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## goalcreas (Nov 20, 2006)

PH Monitor right?


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## ray-the-pilot (May 14, 2008)

goalcreas said:


> PH Monitor right?


What is a PH Monitor?


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## helgymatt (Sep 12, 2007)

a pH monitor monitors pH


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## goalcreas (Nov 20, 2006)

A PH controller monitors PH and turns on / off the co2 based on your set points and is how you usually control the co2 automatically.
Just wondering if your paper is on how to set up a pH monitor / controller (like the Milwaukee SMS 122) to control the co2 because I have never heard of a co2 controller.
I guess if I were to read your paper, I would get my answer.


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## helgymatt (Sep 12, 2007)

A pH monitor just gives a single point reading of pH.

pH controllers adjust CO2 to keep the pH at a certain point.


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## goalcreas (Nov 20, 2006)

Yep, I realize my mistake of saying monitor when I meant controller.

After reading some of the papers, is this thing actually a Co2 controller measuring Co2 and not PH.
He was adding PPM's of Co2 levels to the water but still seems to be measuring PH, not Co2.

But this might be a more accurate way to calibrate the PH probes instead of using PH solutions.
IDK, is it? good idea though.


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## helgymatt (Sep 12, 2007)

goalcreas said:


> After reading some of the papers, is this thing actually a Co2 controller measuring Co2 and not PH.
> He was adding PPM's of Co2 levels to the water but still seems to be measuring PH, not Co2.


I got out of it that he was using a pH monitor and measuing pH after he had added so much CO2 to the tank. But who knows? Its published though... I don't know where....Aquatic Plant Central?



goalcreas said:


> But this might be a more accurate way to calibrate the PH probes instead of using PH solutions.
> IDK, is it?


No its not! Try explaining this one to the scientific community....LOL. pH solutions are known standards. No one could mix up a little CO2 into water and come nearly as accurate as pH calibration standards. Remember CO2 is a gas and when dissolved in water it will very quickly gas off.


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## goalcreas (Nov 20, 2006)

OK, I buy that, sounded technical in his paper though.

I guess I meant that since he knows the co2 levels exactly (I guess he wouldn't, but the way he set up his control sounded sound) then you can set your probes to that known level and you would be measuring the co2 more then the PH it is calculated out at.
IDK it sounds interesting, but I am really tired at this point, so IDK much anymore. LOL


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## goalcreas (Nov 20, 2006)

OH, one last thing, I think he said he was adding PPM's of carbon, not Co2, so now I have more then confused me, and maybe you and everyone else


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## helgymatt (Sep 12, 2007)

Yes, its just one big wad of confusion...thats all. 

pH probe will only ever measure pH. However, as he pointed out CO2 is in direct relationship with pH and KH. I think Ray agrees with that more or less. Therefore, I don't know why calibrating a pH meter to CO2 standards would ever need to be done.


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## ray-the-pilot (May 14, 2008)

helgymatt said:


> Yes, its just one big wad of confusion...thats all.
> 
> pH probe will only ever measure pH. However, as he pointed out CO2 is in direct relationship with pH and KH. I think Ray agrees with that more or less. Therefore, I don't know why calibrating a pH meter to CO2 standards would ever need to be done.


Let me rephrase your question using a mercury in glass thermometer as an example.

A mercury in glass thermometer will only ever measure the volume of mercury in the tube. However, as he pointed out the mercury volume is in direct relationship with the temperature. I think Ray agrees with that more or less. Therefore, I don't know why calibrating a mercury in glass thermometer to temperature standards would ever need to be done.


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## helgymatt (Sep 12, 2007)

Whats wrong with pH calibration standards?


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## ray-the-pilot (May 14, 2008)

helgymatt said:


> Whats wrong with pH calibration standards?


If I were using a thermometer to measure volume I'd calibrate it using volume standards. If I were using it to measure temperature, I'd use temperature standards.

Since I am interested in the absolute level of CO2, I think that it is appropriate to use CO2 standards, don't you?


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## helgymatt (Sep 12, 2007)

No. Thermometers don't measure volume. CO2 lowers the pH that is why you see a response on the pH meter.

Who is going to mix up a pail of CO2 water when they want to quickly and easily calibrate their pH meter?. Although your method may work to calibrate your meter it is not user friendly. There is so much error in your method it is not even funny. You are weighing CO2??? Remember how easily CO2 outgases from water....another source of error during your calibration! I would guess more error than any phosphate buffers or anything else could have. Also, do you calibrate at different CO2 concentrations or just one?


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## ShaneSmith (Feb 15, 2004)

Ray, why do you think there is a difference in distribution of co2 in your tank versus Thomas Barrs? If you inject co2 into a system the same why don'twe see the same distribution problems? I think you need to fully analyze the difference in your filter and diffusion systems, if they were the exact same things would make more sense to me at least. I am confused by your write-ups. He injects co2 gets diffused in filter and he gets highest readings at filter outlet, makes sense. as the water flows is seems to lose co2 concentration. Your system seems to dispurse the high co2 water much better than his.


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## ray-the-pilot (May 14, 2008)

ShaneSmith said:


> Ray, why do you think there is a difference in distribution of co2 in your tank versus Thomas Barrs? If you inject co2 into a system the same why don'twe see the same distribution problems? I think you need to fully analyze the difference in your filter and diffusion systems, if they were the exact same things would make more sense to me at least. I am confused by your write-ups. He injects co2 gets diffused in filter and he gets highest readings at filter outlet, makes sense. as the water flows is seems to lose co2 concentration. Your system seems to dispurse the high co2 water much better than his.


I've already answered this question here:

http://www.aquaticplantcentral.com/forumapc/equipment/57094-would-you-want-live-wood-burning.html

The simple answer is this:

Tom Barr reports CO2 all over the place using his system. I report CO2 is the same all over the place using mine. Both of these are scientific facts Ie data. Why this difference exists is a hypothesis and is subject to opinion. The fact is you can get better CO2 distribution using a CO2 controller.

If you really want to understand this better, send me a PM and I'll explain why this is so.


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## pjbc (Jun 28, 2005)

Hi Ray,

To keep the things On-Topic, I moved my post from the other thread to this one.

*ray-the-pilot: *
I don't know why but I can' open your word document's!

But are you comparing values from your setup with values from Tom Barr tank setup?
(I didn't read Tom Barr post that you linked.)

But the values and conclusions can not be compared they are from completed different setup's!

Can I propose you to do the following experiment?[smilie=i:
(I can't do it because I broke my PH Controller and I have my co2 running without it.)

1) Trim the plants like you usually do.
2)Take a picture of you tank.
3)Run you tank with the ph controller for a week.
4)Measure the PH in your tank in 5 or 6 points, in the morning in mid-day and at night before lights go off.

This is the second part of the experiment:
5) Unplug the PH controller from the solenoid valve, use it only to measure PH.
6) Open or close your co2 needle valve until you have the desired PH/co2 level in one spot.
(this may take some days, start low and go high until desired value.)
7) Using the picture you have taken the week before, cut your plant to the same size.
8 ) Run the tank without the controler for a week.
9) Measure the PH at the same time of day and same point you measured in 4)

10) post this measurements here! 

Almost for sure you will get this conclusions:
-With controller the PH will not fluctuate much, maybe 0,2PH(?)
-Without controller you have bigger PH fluctuation, maybe 1PH,
but you will have the same death/hot spots than you had with controller.

Do you accept this "challenge"? [smilie=n:

([B]I did'nt read this thread yet.... give me 1 or 2 days... to update my readings![/B])


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## helgymatt (Sep 12, 2007)

^ If I were to guess...I would say it won't be accepted. 

Ray, you report some ares of the tank have 17 ppm CO2 and others have 24. Is there a statistical difference between these two values? Yes or No, and show me the stat report.


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## goalcreas (Nov 20, 2006)

ray-the-pilot said:


> The fact is you can get better CO2 distribution using a CO2 controller.


Ok, now I am much more confused them before, and not by the science at all.
My initial question (though it might not have been clearly stated as a question and I mistakenly called it a monitor when I meant controller) was:

Do you mean setting up a PH Controller or a Co2 Controller.?

There, that is more clear, at least should be.

Now, I am not aware of a product called a Co2 Controller. Am I missing something. Is there a product out there that is a Co2 Controller that I am not aware of and is that what you are talking about here.

Not trying to get cute and not trying to start trouble, I am just wanting to know if I am out of the loop, or if you are calling a PH controller a Co2 controller?

If you ARE IN FACT using a PH Controller, I don't see how your quoted statement could be accurate because the monitor only turns on and off the solenoid.

However if there is a co2 controller and it does do what you claim, then I am interested in learning about the product, how much do they cost, where do you get them, DO THEY GIVE you better distribution.

IME a reactor gives better distribution then a diffuser, so I have been using them.
IME a controller protects against over gassing.


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## BryceM (Nov 6, 2005)

There seems to be quite a bit of confusion regarding this post. Might I attempt to throw in my two bits and clarify a couple of things:

First, Ray is indeed talking about using a pH controller. If you assume that KH is constant, there is a well-established relationship between CO2 concentration and pH.

One thing that Ray has done that other people haven't, is to use a "standard" 8100 ppm CO2 solution. I'm not familiar with this particular seltzer tablet that he's using. If it does indeed contain 8,100 mg of CO2 (once dissolved) it should create the reference solution he's talking about. If instead, only a portion of a 8.1 gram tablet dissolves to CO2 then the actual stock solution will be less than 8,100 ppm. Unless he's using pure dry ice, only a portion of a tablet will convert to dissolved CO2. It also seems unlikely to me that you can dissolve 8 grams of CO2 in a 1 liter bottle "alka-seltzer style" without exploding the bottle, but that's just my gut feeling.

I'd also be hesitant to apply his results to all aquariums. One experiment in one particular aquarium provides evidence of a single anectodal event, not universal proof of a concept.

His point about the variability of CO2 concentration in an aquarium is an important concept. I'm inclined to side with Tom Barr on this one. It all depends on circulation patterns, turbulence, internal mixing, and the velocity of the water column.

To sum up my feelings, accurate CO2 measurement is next to impossible at a hobbyist level. I agree that controllers can be a useful tool. To use one correctly, KH must be stable, the probe needs to be calibrated frequently, the probe needs to be replaced when necessary, and you need to gradually decrease the pH while monitoring plant response and fish stress. More flow equals more circulation which creates better CO2 mixing and distribution.


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## goalcreas (Nov 20, 2006)

BryceM said:


> First, Ray is indeed talking about using a pH controller.


Thanks Bryce, that is what I was looking for.


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## helgymatt (Sep 12, 2007)

goalcreas said:


> Ok, now I am much more confused them before, and not by the science at all.
> My initial question (though it might not have been clearly stated as a question and I mistakenly called it a monitor when I meant controller) was:
> 
> Do you mean setting up a PH Controller or a Co2 Controller.?
> ...


There is no such thing as a CO2 controller, at least in the aquatic plant hobby. There is a CO2 MONITOR which can measure "real-time" CO2 concentrations. Will cost you $1000+ to buy one of those. That is what Tom Barr uses to measure the different areas of his tank to determine variation in CO2 concentrations in different areas of his tank.

A pH controller will not give you better CO2 distribution. Only good flow and circulation will do that. Plain and simple...The author of the thread is trying to prove otherwise. What a pH controller can do is provide a STABLE CO2 and pH concentration. But, the author has data from HIS tank that seems to show CO2 concentrations are the same all over the tank. He must have good flow to equilibrate the CO2 around the tank. Two things _I_ believe the author is confusing are (1) the ability of a pH controller to somehow magically equilibrate the CO2 and (2)the function of a filter/pump.


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## ray-the-pilot (May 14, 2008)

BryceM said:


> One thing that Ray has done that other people haven't, is to use a "standard" 8100 ppm CO2 solution. I'm not familiar with this particular seltzer tablet that he's using. If it does indeed contain 8,100 mg of CO2 (once dissolved) it should create the reference solution he's talking about. If instead, only a portion of a 8.1 gram tablet dissolves to CO2 then the actual stock solution will be less than 8,100 ppm. Unless he's using pure dry ice, only a portion of a tablet will convert to dissolved CO2. It also seems unlikely to me that you can dissolve 8 grams of CO2 in a 1 liter bottle "alka-seltzer style" without exploding the bottle, but that's just my gut feeling.


Never trust your gut!

http://www.prairiemoon.biz/isibrusalsyp.html

BTW Don't you own a CO2 controller?


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## goalcreas (Nov 20, 2006)

Do you have a link to the Co2 controller?


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## ray-the-pilot (May 14, 2008)

goalcreas said:


> Do you have a link to the Co2 controller?


If you want to duplicate my system use the UltraLife MC101 controller:
http://www.ultralifedirect.com/ph&orpcontrol.htm

If you just want to control your CO2 you can use the UltraLife M301 or this Controller:
http://www.aquariumplants.com/Automated_pH_Co2_Controller_MILWAUKEE_SMS122_p/pr209.htm

I purchased my MC101 at my LFS and it was less expensive than the on line price. Who knows?


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## goalcreas (Nov 20, 2006)

OK, yeah, that is a PH Controller.
Which is what I thought it was back in my first post.
It is a Co2 controller in the sense that we hook them up to Co2, but really it controls anything powered based on PH set points. I could turn on / off my living room lamp based on the PH in my tank. (realizing that the light won't do anything to change the PH in my tank, but I could do it based on the natural fluctuating of the PH in the tank)
I do see now that other places are calling them PH / Co2 controllers to market them in the hobby.
I have enough success IMHO just using it with PH calibration to not want to go the extra steps you do, but it is an interesting concept.


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## chiahead (Dec 18, 2004)

again its not a Co2 controller both of those are using a ph probe to control ph...thus it is a ph controller.....its only activating or turning on the co2 when the ph is outside of the range you set it at


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## helgymatt (Sep 12, 2007)

Always trust your gut!


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## BryceM (Nov 6, 2005)

After a PM from Ray-the-Pilot I went back and looked at the Seltzer bottles and chargers more carefully. It wasn't immediately obvious (to me at least) from the link or from the article what he was using. His referenced link lists two alka-seltzer type tablets and one CO2 charging container similar to a disposable paintball cartridge. Apparently he is using the small canister.

I will agree that his method adds 8.1 grams of CO2 to the seltzer canister. Atmospheric CO2 concentrations are on the order of 3 or 4 ppm, a minor error at this point. I'm not so sure the 8.1 grams of CO2 are completely contained in the liquid portion of the canister's contents. If there is an air gap above the fluid level, a fairly significant portion of the CO2 will not be dissolved, leaving the CO2 concentration of the liquid stock solution lower than 8100 ppm. Once all of the fluid from the canister is discharged there will still be a large quantity of gaseous CO2 in the bottle.

Another potential source of error lies in the fact the the aquarium has 3 or 4 ppm of dissolved CO2 prior to starting the experiment. As far as I can tell, the calculations do not account for this. When added concentrations are on the order of 20 or 30 ppm, this will introduce an error of roughly 10 percent.

Rays experiment does demonstrate that in his aquarium there is a reliable (almost linear) relationship between various quantities of added CO2 and a measurable drop in pH. From my understanding of CO2 dissolution and carbonate buffering, this observation should be correct. His own particular aquarium seems to have been set up such that a uniform distribution of CO2 is achieved. This is a function of plant density, flow rates, turbulence patterns, and perhaps limitations in the ability to measure a difference in local pH levels (and therefore CO2 concentration) if differences do exist. As far as I can tell, this property of his aquarium is a result of the particular fluid mechanics in that system and not a result of having used a pH controller.

Finally, and perhaps most importantly, it must be understood that these devices are in fact, pH controllers and not CO2 controllers. Advertisers may market them under any name they choose, but the underlying mechanism of action is the same. They measure pH and the solenoid acts to effect a change in pH - in this case by addition of CO2. In a stable system (one with no change in acid production, buffering systems, or probe calibration) a pH controller acts well enough as a CO2 controller. We know, however, that aquariums are far from stable. Biological process produce large quantities of organic acids. The nitrogen cycle is just one example of how this occurs. The carbonate buffering system is the largest and most important in the aquarium, but other buffers exist and contribute.

The pH/KH/CO2 relationship described by Chuck Gadd and others does work. It is accurate, however, only in distilled water with carbonate as the only buffer, and no acid apart from that produced from CO2 addition. Some aquariums approach this condidion more closely than others. If your aquarium's KH and pH give a value of 30ppm CO2 on the chart you would be wise to consider than your actual CO2 levels may be FAR lower than this.


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## helgymatt (Sep 12, 2007)

Yes, lots of error as I said!


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## helgymatt (Sep 12, 2007)

Ray,

I pulled this quote of yours from another thread:

"You will see that there is only a statistically insignificant variation in CO2 levels in a typical CO2 controlled tank."

Interesting claim. I ran the stats on your data and found strong evidence that CO2 concentrations in your tank vary both by location and day. Attached is output from the Statistical Analysis Software (SAS) commonly used in academia to statistically compare means. For example, position 1 has a lower CO2 concentration than positions 2, 3, and 6. Position 6 has a higher CO2 concentration than positions 1, 4, and 5. As one would expect, position 6 (which has the highest CO2 concentation) is right at the output of the filter, and position 1 (which is upstream from the filter output) has the lowest concentration. This evidence suggests that there are differences in CO2 concentations throughout the tank and that areas which recieve less flow will have lower CO2.

Although these differences observed in your tank are small, they are consistent and real. Your claim that pH meters lead to "only a statistically insignificant variation in CO2 levels" is not supported by your data. Again, this data is only representative of _your_ tank and others, who may have less flow in their tank, will likely have even larger differences found. I suggest in the future that you base your scientific claims on the conventions of science.

http://i254.photobucket.com/albums/hh100/helgymatt/statsisticalanalysisofCO2_1.jpg
http://i254.photobucket.com/albums/hh100/helgymatt/statsisticalanalysisofCO2_2.jpg

EDIT: If anyone wants an explanation of the analysis here I would be happy to explain it.


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## BryceM (Nov 6, 2005)

Ray,

The point here isn't that we're trying to tear down your ideas or your data. It's actually very refreshing to see someone doing some independent research. This is far more useful than people spouting off "so and so" just because they've read it a dozen times from other people.

The important point here is that you've drawn conclusions from your data that might not stand up to careful scrutiny. That's OK. Refine the data, your techniques, and make your points. The discussion here is friendly, I ensure you. We're all after the same end result, which is a better understanding of how to make our aquariums do what we want them to.

None of us understand this CO2 principle perfectly. If we did, there would be no need for discussions like this one. I happen to use a CO2 controller and I really like it. I'm aware that its use has several potential problems though. They really need close babysitting to work well over long periods of time.


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## goalcreas (Nov 20, 2006)

Well said Bryce.
I agree fully.
I was not trying to belittle you by pointing out it is a PH Controller, rather
I was just clarifying for my own understanding weather you are using a PH controller or if 
there was something I did not know about called a Co2 Controller.
I have gotten my answer, fully satisfied with it and wish you the best of luck on this project as you refine it and look forward to seeing others you present in the future.


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## ray-the-pilot (May 14, 2008)

helgymatt said:


> Ray,
> 
> I pulled this quote of yours from another thread:
> 
> ...


While your analysis is good it is not valid. The reason this is true is because the data is not normally distributed. The data has been manipulated through a logarithmic algorithm. This skews the distribution.

If you PM me I will share the actual data with you and you can run it through your program.

Have a nice day!


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## ray-the-pilot (May 14, 2008)

Thanks for editing your comments. I plan a longer reply but I do not have time now. I do have one question however, that needs an answer.
You write:



BryceM said:


> After a PM from Ray-the-Pilot I went back and looked at the Seltzer bottles and chargers more carefully. It wasn't immediately obvious (to me at least) from the link or from the article what he was using. His referenced link lists two alka-seltzer type tablets and one CO2 charging container similar to a disposable paintball cartridge. Apparently he is using the small canister.


If this isn't clear I need to change it but I'm confused by your comment.

This is what I wrote:

Preparation of a 8,100 ppm CO2 Solution.
Using a graduated cylinder, I added exactly 1 L of distilled water to the ISI Seltzer bottle.
A standard 8 gram CO2 charger was weighed to three significant figures. 
Following the mfg. directions, the seltzer bottle was charged and shaken well. The charger was reweighed. The difference 8.10 gm indicated that the CO2 solution was exactly 8,100ppm. The CO2 solution was refrigerated for 24 hr prior to use.
And here is the link:

http://www.prairiemoon.biz/isibrusalsyp.html

I don't get the alka-seltzer type tablets? Where is this?

I could be wrong (and I often am) but I think that is what Tom Barr used in his study.


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## BryceM (Nov 6, 2005)

I dunno. :noidea: Maybe I was looking at something else while trying to figure out what you were using. After looking at it again it was obvious you were using small CO2 canisters. That part of your experiment made much more sense once that was clear in my head. Other people have used dissolving tablets to create CO2 solutions.


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## helgymatt (Sep 12, 2007)

ray-the-pilot said:


> While your analysis is good it is not valid. The reason this is true is because the data is not normally distributed. The data has been manipulated through a logarithmic algorithm. This skews the distribution.
> 
> If you PM me I will share the actual data with you and you can run it through your program.
> 
> Have a nice day!


Is the data in your report adjusted or is that the actual data? If it's the actual data, I checked the distribution before analsysis and it is normal. I can show you the results tomorrow. If the data in your table is in fact the logarithmic algrithm, I don't know why you wouldn't have noted to that.


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## ray-the-pilot (May 14, 2008)

helgymatt said:


> Is the data in your report adjusted or is that the actual data? If it's the actual data, I checked the distribution before analsysis and it is normal. I can show you the results tomorrow. If the data in your table is in fact the logarithmic algrithm, I don't know why you wouldn't have noted to that.


Actually I did note this in my paper. Maybe I should have put it in BOLD!

<<H2CO3 and kH are the same as before but H+ is the hydrogen ion concentration You can find the H+ concentration from the pH by using this math manipulated H+ = 10^(-pH)
Using this manipulator and plugging in arbitrary values of pH into Chuck's equation you get the results shown in Table 1 which is graphed in Fig. 1.>>

Have a nice day!


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## helgymatt (Sep 12, 2007)

ray-the-pilot said:


> Actually I did note this in my paper. Maybe I should have put it in BOLD!
> 
> <<H2CO3 and kH are the same as before but H+ is the hydrogen ion concentration You can find the H+ concentration from the pH by using this math manipulated H+ = 10^(-pH)
> Using this manipulator and plugging in arbitrary values of pH into Chuck's equation you get the results shown in Table 1 which is graphed in Fig. 1.>>
> ...


No, your values for CO2 should work just fine for analysis. Your transformation from pH to CO2 is simply a unit conversion, and both the variances and distribution of these data are normal. The fact that you have to use a formula, which includes pH and KH, to calculate CO2 suggests that the CO2 values can be analyzed without transformation. If you had more data points, the distribution would look even better, but for the data points you have, this is quite good.

You cannot make scientific claims until you have solid statistics to back them up. I have requested to see some statistical analysis from you several times but get nothing in return so I have done these analyses for you.

I'm getting a sense that no matter what I or anybody else says about this topic will get rejected. If you fail to accept anyone else's criticism of your methods and interpretations (which is the foundation of good ethical science) then I can no longer participate in this argument.

Also, I see no reason to have to PM you for information. If you are presenting a technical paper and saying that you have done statistical analysis and making "scientific" claims it needs to be presented to everyone. I assure you I am not the only one around here who understands science and others would like to see exactly how you have come to these conclusions.

















EDIT: The blue line represents a normal distribution and the yellow line is the distribution Ray's data follows. As you can see, the distribution is very close to normal and nothing to be concerned about statistically.


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## ray-the-pilot (May 14, 2008)

helgymatt said:


> No, your values for CO2 should work just fine for analysis. Your transformation from pH to CO2 is simply a unit conversion, and both the variances and distribution of these data are normal.


I think you need to talk to your statistics professor on this one.

A logarithmic manipulation is a non-linear transformation of the data, which does not preserve the distribution characteristic of the data. You can verify this yourself with a simple test. 
Start with this set of 100 points:
S1 = {1.0, 1.1. 1.2, &#8230;.9.8, 9.9 10.0}
If you plot the distribution of this data it obviously has a uniform distribution.

Now take the log of each data point and get a new set:
S2 = {0.0, 0.041, 0,079, &#8230; 0.9912, 0.9956, 1}
If you plot this set you will see that it is no longer uniform.

Actually I can take criticism very well. Unfortunately, your understanding of this problem is not up to speed. This is actually a very complicated statistics problem and does not resolve with the simplistic approach you are using.

This stuff is way beyond what anyone else on this board is interested in. I am more than willing to work with you. PM me and I will share my data with you and discuss the issues. Otherwise, Have a nice day.


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## helgymatt (Sep 12, 2007)

First off, stop trying to be cute and telling me to have a nice day please. I'm not here to play games with you or try to prove something. I am a scientist and like most scientists I question the validity of scientific claims that you say will "change and revolutionize" the hobby.

Clearly we are at odds. Based on the YOUR data and based on THE tests for normality, your data are in fact normal. And no, I don't need to talk to my stat professor. I spent 2 years with him learning the analysis of variance, the assumptions (normality, equal variance, and independence) required for the analysis, and the tests to check to make sure the assumptions hold strong. *If the "statistical problem" is so complicated, how have you possibly come to your conclusions? *How can you argue all this statistical stuff without presenting a single bit of statistical evidence?

I rest my case. Good luck trying to convince others of this.

For everyone else's record, the analysis _I_ have done for Ray shows no evidence that a pH controller leads to total equalization of CO2 levels throughout an aquarium. Until Ray presents anything that suggests otherwise, take all this with a grain of salt.


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## helgymatt (Sep 12, 2007)

edit


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## ashappard (Jun 3, 2006)

A thread like this makes successful CO2 injection seem _way_ more difficult than it really is.
it may make a newcomer think that a controller is essential for success.

possibly because the final conclusion in your paper is that "If you are trying to maintain the CO2 in your aquarium at the optimum level for plants and fish, then a CO2 controller is essential."

no offense Ray, I know you are trying to spread info and help. But I beg to differ.
I'm not a scientist, dont want to be, and can't attempt to discuss all the stats and whatnot.

the main things I see missing in setups that show evidence of poor CO2 are

1> consistent flow that reaches the plant beds (to maximize distribution)
2> consistent metering with a good needle valve (for stable control)
3> proper mixing of CO2 into the water column (for quick response)
4> minimal surface agitation (to maximize retention)


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## BryceM (Nov 6, 2005)

And on the discussion goes.

Please, lets keep it nice, clean, and civil. Otherwise the thread will be closed.


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## ray-the-pilot (May 14, 2008)

ashappard said:


> A thread like this makes successful CO2 injection seem _way_ more difficult than it really is.
> it may make a newcomer think that a controller is essential for success.
> 
> possibly because the final conclusion in your paper is that "If you are trying to maintain the CO2 in your aquarium at the optimum level for plants and fish, then a CO2 controller is essential."
> ...


Well those may be what works for you and I cannot argue with them but in the test tank that I used:

I did do something to maintain good flow by using a filter rated above my tank size.
I didn't use a needle valve.
I didn't do any special mixing except as noted below.
I did consistantly use significant aeration to maintain levels of O2.


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## Supercoley1 (May 28, 2007)

I didn't know there were so many threads on this subject from the same author.

Ray - Are you trying to promote your 'published papers' to try and sell something or gain royalties?

I don't understand why you defend your paper's assumption when we all know that Ph drops within tank water cannot wholly be attributed to CO2!!! This is why the DC users put 4dKH in their DCs and not tank water.

Therefore a Ph controller making this assumption is about as useful as a drop checker with tank water in it!

As for a Ph controller meaning that the ppm is equal all the way around the tank. Is it on some sort of mechanism that uses the probe as a stirring stick and gently mixes the tank water? Or does this system have it's own current devices (powerheads, pumps, filters etc) attached to it?

I think you need to give this one up because you will lead many many people to an algae laden tank!!!

AC


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## ray-the-pilot (May 14, 2008)

Supercoley1 said:


> I didn't know there were so many threads on this subject from the same author.
> 
> Ray - Are you trying to promote your 'published papers' to try and sell something or gain royalties?
> 
> ...


The reason I am so excited about this is because I know a good thing when I've ACTUALLY USED IT! I'm sorry if that seems rude and I apologize for the caps but when you use something you have a different perspective from someone who hasn't.

I just want to point something out. I realize that this may be semantics but it is important in science to understand definitions; so, we are all talking the same language. 
These are the definitions that I use in my papers:

A CO2 controller is an electronic device used to maintain some fixed level of CO2 in an aquatic system.

This is not the same thing as a pH controller. Typical pH controllers are linked to devices that pump dilute solutions of HCl or NaOH and are designed to maintain the pH of an aquatic system.

I do not have a pH controller in my tank. I have a CO2 controller.

In my experiment I did not use any special devise to mix the tank water other than normal filtration. You can find the information about the tank in my profile.

I understand that CO2 is not entirely a function of pH that was the purpose of developing the calibration curve.

I do not have an algae laden tank. Quite a few people (even some moderators) use CO2 controllers in their systems and do not have any more problems with algae.

I have not made any money off of anything I've written in this forum.


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## Supercoley1 (May 28, 2007)

How is it measureing CO2 then? Please explain. I do not understand science so papers with loads of spiel in them mean as much as a bloke wittering on to me in a pub with a drunken slur!!! Therefore I tend to tak no notice of either. Why do you call it 'Ph controlled pressurised CO2 in all your other posts?

Please explain.

I still fail to comprehend how with the same current flow, wether the 'CO2 controller' works or not how with the 'CO2 controller' in the tank the CO2 ppm will be equal all around the tank where a tank without would have deadspots??? No matter if you inject for the whole photoperiod or use a controller the ppm will be higher in the proximity of the source of the CO2 than it is in other areas. This is basic science!!! We can try and push it around the tank quicker but by the very nature of physics where the source is will have huge amounts before it is diluted into the rest of the tank. No science can disprove this!!!

How does the 'CO2 controller' level this out?

And I would like to add following on from the closed thread on this subject we users of non controller tanks do not need to constantly adjust out levels!!! We adjust it over a couple of days at the beginning and then leave it virtually until the bottle runs out!!!

Oh and please post up a picture of your tank for us to see 

I also notice that a lot of your threads are aimed at dismissing either drop checkers in general or high CO2 injections. You seem to suggest that at 15ppm fish are visibly affected!!!! My DC near the source is continually lime green to yellow. The DC at the other end is continually lime green (lower further away ) They both have 4dKH (bought from a reliable source and laboratory tested) which indicates I am in the 25-40ppm region.

Please can you explain why my shrimp colonies are out of control and the Black Corys spawn every 6 days!!! Before you ask no they are not infertile. The wrigglers go in the nursery tank when they are 1 week old!!!

AC


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## BryceM (Nov 6, 2005)

Is there a single person who has read this that thinks Ray has a CO2 controller?

I don't. The piece of hardware he's using doesn't even measure CO2.


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## BryceM (Nov 6, 2005)

ray-the-pilot said:


> Quite a few people (even some moderators) use CO2 controllers in their systems and do not have any more problems with algae.


I use a pH controller and I'm having loads of algae problems.  It's a piece of hardware, like all the other stuff we use. It isn't magic, it has significant limitations, and it works well when used correctly.


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## Supercoley1 (May 28, 2007)

Bryce - I would suggest using you Ph controller as a safety cut off (set it 1.2Ph lower than normal) and then trying the dreaded inject for the photoperiod method (2 hours prior on, and the off 2 hours prior to finish.) Take your DC (or buy one) to light green and then post your results here 

Make a basic (near enough to give the desired colours) 4dKH solution:
6g Bicarb + 5000ml DI water = 40dKH
10ml 40dKH + 90ml DI water = 4dKH

Don't change anything else. Just change the CO2 control method to not controlled.

This is of course assuming you have adequate flow within the tank.

I have 2200lph (on paper) on my 125Ltr tank!!!

AC


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## freydo (Jan 7, 2006)

ray-the-pilot said:


> This is not the same thing as a pH controller. Typical pH controllers are linked to devices that pump dilute solutions of HCl or NaOH and are designed to maintain the pH of an aquatic system.
> 
> I do not have a pH controller in my tank. I have a CO2 controller.


okay... now i'm really confused. you say you have a co2 controller, but in your paper the equipment you list is a UltraLife pH Controller, Model MC 101. looking at the manufacturer's website, they list it as a pH controller.

so what do you have? i don't know if you're purposely trying to confuse people, or you've confused yourself. because right after you've listed off the equipment used in your experiment, you immediately refer to it as a co2 controller.

personally, i think this paper was rushed, and all information that should be included, was not. being a non-scientist, i would personally like to know the basic setup of the tank used, and accompanying photos would have been helpful.

after reading your paper, it still hasn't convinced me that a pH controller (co2 controller) is necessary or useful. or how it can provide better information than basic plant and fish observations with my own eyes.


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## ray-the-pilot (May 14, 2008)

BryceM said:


> Is there a single person who has read this that thinks Ray has a CO2 controller?
> 
> I don't. The piece of hardware he's using doesn't even measure CO2.


As I said this is a question of semantics but an important one. There are pH controllers on the market that are used to control pH. They do not use CO2. I use my controller to control the CO2 level in my tank. It runs on CO2.

Here are some questions.

Does a thermometer measure temperature? 
Does your speedometer measure speed?
Does your pH meter measure pH?

No to all of them.

A thermometer measures volume.
A speedometer measures RPM.
A pH meter measures Oxidation Reduction Potential (ORP a fancy way of saying voltage.)

What a device actually measures has nothing to do with what it controls.

I have a chart next to my controller that converts the readings on the meter to ppm CO2. This is pretty extreme. Most people who use CO2 controllers have a mental chart in their head. A reading of 5.5 is yellow on their drop checker. A reading of 7.0 is blue on their drop checker. (The numbers are not absolute just examples).

I don't think anyone who has a controller is using it to control the pH.

Bruce, I know you have a controller from your posts. Do you use it to control the pH of your tank or the CO2?

I'm sure this is just mindset but I believe that in the future more and more dealers will be advertising their equipment as CO2 controllers because that is what they do.


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## ray-the-pilot (May 14, 2008)

BryceM said:


> I use a pH controller and I'm having loads of algae problems.  It's a piece of hardware, like all the other stuff we use. It isn't magic, it has significant limitations, and it works well when used correctly.


Well, I agree, people have algae problems all the time. That is I why I'm suggesting using a CO2 controller. The more things you can stabilize the more likely you are to find the thing that triggered the algae bloom.

I was reading your thread about the bloom and the only suggestion that I would make is to lower your CO2 so your DC is blue-green and keep the CO2 on 24/7. That's what I do but then I live with a low level of GSA.

Does anyone really know what they are doing in this hobby?


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## ray-the-pilot (May 14, 2008)

freydo said:


> okay... now i'm really confused. you say you have a co2 controller, but in your paper the equipment you list is a UltraLife pH Controller, Model MC 101. looking at the manufacturer's website, they list it as a pH controller.
> 
> ............
> or how it can provide better information than basic plant and fish observations with my own eyes.


I could be wrong about this (I frequently am) but I think the UltraLife people call it a pH/ORP controller. ORP is a fancy way of saying that it can control anything that changes the ORP (voltage) like CO2. 
I understand this is confusing but that is why I am calling it a CO2 controller because it controls the CO2 in my tank to +/- 2 ppm.

I don't think this is "better information than basic plant and fish observations with my own eyes." 
This is just a suppliment to and a confirmation of that information.


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## BryceM (Nov 6, 2005)

Ray,

So you're a believer in the CO2 chart eh?

Answer me this:

Do you believe the pH/KH/CO2 concentration chart to be valid for aquarium conditions? If it is, then you might, in fact, be able to argue that the device functions as a CO2 controller.

If, however, there are potential sources of error inherent to the pH/KH/CO2 concentration chart, you must admit that your device can't possibly be reacting only to changes in CO2 concentration. It is measuring only pH (or ORP if you'd like), a surrogate marker for CO2 (and not a very good one IME). A measurement of mercury volume in a thermometer is an excellent surrogate for temperature. It's scarcely affected by any other variable. Any acid-base chemistry that takes place in the aquarium will affect the pH of the water, introducing an error to the supposed measurement.

The KH/pH/CO2 chart is only valid for a carbonate buffer system in distilled water with added CO2 as the only source of acid. Add in any other variable such as secondary buffering systems, acidification via the nitrogen cycle, or a myriad of other biochemical acid/base processes and the chart is quickly invalidated. Assume then that the biological acid/base processes might not be constant over time and you'll see actual CO2 concentrations wandering all over for a given pH and KH. Thermometers and speedometers aren't subject to so many other variables in normal operation.

Your argument of semantics proves nothing to me except that you don't have a good grasp of the potential sources of error inherent to the device.

OK.

I've said my piece. I'm unsubscribing to this thread since I see no further value in discussing the subject with those unwilling to consider a broader point of view.


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## freydo (Jan 7, 2006)

ray-the-pilot said:


> I could be wrong about this (I frequently am) but I think the UltraLife people call it a pH/ORP controller. ORP is a fancy way of saying that it can control anything that changes the ORP (voltage) like CO2.
> I understand this is confusing but that is why I am calling it a CO2 controller because it controls the CO2 in my tank to +/- 2 ppm.
> 
> I don't think this is "better information than basic plant and fish observations with my own eyes."
> This is just a suppliment to and a confirmation of that information.


yeah... but it's still a pH controller. not a co2 controller. and that's not semantics. and referring to it as such, because it's "less confusing", does nothing but slant your "paper" to just anecdotal information that suits your own purpose. and so far, hasn't stood up to any of the requests for additional information and/or clarification.

why you don't provide the information that has been requested, so that it can be confirmed (or refuted), is puzzling. that's the whole point of doing a scientific experiment and publishing the results, so that your peers can review.

unless there's something to hide.


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## ray-the-pilot (May 14, 2008)

freydo said:


> yeah... but it's still a pH controller. not a co2 controller. and that's not semantics. and referring to it as such, because it's "less confusing", does nothing but slant your "paper" to just anecdotal information that suits your own purpose. and so far, hasn't stood up to any of the requests for additional information and/or clarification.
> 
> why you don't provide the information that has been requested, so that it can be confirmed (or refuted), is puzzling. that's the whole point of doing a scientific experiment and publishing the results, so that your peers can review.
> 
> unless there's something to hide.


What information are you asking for????????????????????????????

And it doesn't control pH. It measures ORP and controls the CO2 in my tank.


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## helgymatt (Sep 12, 2007)

Ok...I've waited too long to say this, but you you are a total lunatic and this thread needs to be shut down just like all the other ones! If there is anyone who wants to disagree just to disagree it is you and stop confusing EVERYONE with this false science.

You cannot talk about good science when the science you have done yourself is SO poor. You don't even have a control in your "experiments" which is the most basic principle of all! Your whole point in this thread has already been disproven, but you just keep rambling. Stuff like this will drive people away, just like it is about to do to me!



BryceM said:


> And on the discussion goes.


I hope not. Maybe if anything here actually made sence "scientifically".



BryceM said:


> Please, lets keep it nice, clean, and civil. Otherwise the thread will be closed.


Well, not exactly, but I can't help it. And yes, if I was face-to-face with Ray I would tell him the same thing. This is not some "online" rant I'm on right now, this is just rediculous.


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## jmhart (Nov 13, 2007)

I think the highlight of the thread is the phrase "recently published"

and, a point that I seem to never under stand in all off Ray's pH controller post is what is he trying to say?

I don't think anybody disagrees that pH controllers can be used to control co2 concentration inside the tank. What's the problem here?


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## helgymatt (Sep 12, 2007)

Read the thread...
He is trying to prove pH controllers are better than drop checkers because controllers lead to a total equilibration of CO2 throughout the aquarium. Not true, no "scientific proof". Period.


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## helgymatt (Sep 12, 2007)

ray-the-pilot said:


> What information are you asking for????????????????????????????
> 
> And it doesn't control pH. It measures ORP and controls the CO2 in my tank.


Well I would have like that scientific proof you are claiming and stat analysis, but I don't really care anymore.

BTW, where do I pick up a CO2 controller?


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## Tex Gal (Nov 1, 2007)

Ok guys.... I can't imagine there is anything left that is worth saying so why not let's just move on. Please don't start a new thread to continue this same subject. Thanks guys! This thread is closed.


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## BryceM (Nov 6, 2005)

Thanks Tex.

It was time to give it a proper burial.


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