# DIY CO2 diffuser question.



## Lono (Aug 15, 2006)

I recently purchased a Hagen CO2 kit.
I'm starting to question the effectiveness of the ladder defuser.
I was wondering if anyone thought that my new idea would work.

I have an AC Powerhead that I've rigged up with a sponge attached to the input. I was wondering if anyone thought it would be good to cut a slit in the bottom of the sponge and take the tubing from the CO2 and have it running through the bottom of the sponge dispersing the CO2 into the input of the powerhead.

I want to keep the sponge but I also want to use the powerhead to disperse the CO2.


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## John N. (Dec 11, 2005)

Lots of people use the CO2 tubing through the intake of a powerhead and filter intake. One person that comes to mind who uses the exact setup you describe with a sponge over the intake of a powerhead is HoppyCalif. This method works very well. I personally have a glass diffuser underneath an intake to also blow the CO2 around and get them a better chance to dissolve.

Oh Welcome to the Forum Lono! 

-John N.


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## TheSentinel (Jan 25, 2006)

It has been done, but there are a few options with powerheads and CO2. Have you considered using a limewood stone to break up the CO2 into smaller bubbles before it gets into the powerhead? There's also an in-tank venturi reactor which will also include a pop bottle as well as the CO2 mist idea.

If searching the forum doesn't help, let me know and I'll get you some links.


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## Lono (Aug 15, 2006)

John N. said:


> Lots of people use the CO2 tubing through the intake of a powerhead and filter intake. One person that comes to mind who uses the exact setup you describe with a sponge over the intake of a powerhead is HoppyCalif. This method works very well. I personally have a glass diffuser underneath an intake to also blow the CO2 around and get them a better chance to dissolve.
> 
> Oh Welcome to the Forum Lono!
> 
> -John N.


Glad to be here.
I think I'll give it a try in the morning.
I just got my new light set up and I want the best possible 
CO2 dispersion now because I'm ordering plants in the next couple of days.

Thnaks


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## Lono (Aug 15, 2006)

TheSentinel said:


> It has been done, but there are a few options with powerheads and CO2. Have you considered using a limewood stone to break up the CO2 into smaller bubbles before it gets into the powerhead? There's also an in-tank venturi reactor which will also include a pop bottle as well as the CO2 mist idea.
> 
> If searching the forum doesn't help, let me know and I'll get you some links.


I'm wondering if my Hagen semi-DIY Co2 unit has enough pressure to 
produce bubbles through a limewood stone. I think I have a couple in a box around here. Give me the word and I'll slap one on and see what it does.
I could put it right below the spraybar of my canister and totally scrap the Powerhead idea all around.


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## John N. (Dec 11, 2005)

You might get the limewood to work. Best way to know is to try it out. No harm done. Let us know how it works out.

-John N.


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## TheSentinel (Jan 25, 2006)

What size is your tank and what filter do you have? The powerhead might be able to do a better job of getting the CO2 all the way around the tank. If you're in an experimenting mood, you should be able to find out fairly quickly which works better.


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## Lono (Aug 15, 2006)

TheSentinel said:


> What size is your tank and what filter do you have? The powerhead might be able to do a better job of getting the CO2 all the way around the tank. If you're in an experimenting mood, you should be able to find out fairly quickly which works better.


30 gallon tank w/ a Ehiem 2215 and an AC 50


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## redstrat (Apr 3, 2006)

Out of curiosity, have you ever considered a DIY yeast solution to generate CO2, its probably cheaper than going with something pre-prepared like the hagen set up?


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## TheSentinel (Jan 25, 2006)

I'm really not sure what's required to use a filter for circulation, but it looks like your filter is rated for 3x the size of your tank and moves enough water to change your tank over 4x per hour. I'd have to guess that your circulation should be pretty good even without a powerhead.

To be lazy, you could put the limewood stone (if it works for you) right under the intake of the filter and diffuse it that way. People on the Barr Report forum are raving about the CO2 mist idea ie feeding the CO2 into a powerhead into a drilled tube running along the bottom of the back wall of the tank.

Whatever route you take, everything listed in this thread should work well and be fairly easy.


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## Lono (Aug 15, 2006)

davis.1841 said:


> Out of curiosity, have you ever considered a DIY yeast solution to generate CO2, its probably cheaper than going with something pre-prepared like the hagen set up?


Yes


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## Lono (Aug 15, 2006)

TheSentinel said:


> I'm really not sure what's required to use a filter for circulation, but it looks like your filter is rated for 3x the size of your tank and moves enough water to change your tank over 4x per hour. I'd have to guess that your circulation should be pretty good even without a powerhead.
> 
> To be lazy, you could put the limewood stone (if it works for you) right under the intake of the filter and diffuse it that way. People on the Barr Report forum are raving about the CO2 mist idea ie feeding the CO2 into a powerhead into a drilled tube running along the bottom of the back wall of the tank.
> 
> Whatever route you take, everything listed in this thread should work well and be fairly easy.


Limestone thing didn't work but the powerhead worked like a dream!


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## Lono (Aug 15, 2006)

Well I guess my Hagen CO2 kit isn't working out.
My tap PH is 7 and KH is 6
After 4 days of CO2 I get the same readings out of my tanks water!!!
I guess it's a larger DIY set up for me.
Any advice?


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## redstrat (Apr 3, 2006)

you will probably need to add another hagen CO2 generator unit in your system you can do this using "T" airling fittings. how big is your tank can you give some specs maybe I can help you out with a diy set up. I have over 30ppm consistantly in my 75gallon tank using only DIY.


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## Lono (Aug 15, 2006)

davis.1841 said:


> you will probably need to add another hagen CO2 generator unit in your system you can do this using "T" airling fittings. how big is your tank can you give some specs maybe I can help you out with a diy set up. I have over 30ppm consistantly in my 75gallon tank using only DIY.


My tank is a 36" - 30 gallon tank.
Ebo Jager 150w
Eheim 2215
Aqua Clear 50 
Aqua Clear 201 powerhead (CO2 running through that)
Eco Complete substrate
Coralife CF 65w - 6700k bulb

I want to go out tomorrow and buy some stuff to do the DIY set up but I'm still trying to figure it out. ANy help would be greatly appreciated.


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## redstrat (Apr 3, 2006)

As always your milage my vary this is all based on my personal experience, although limited and anyone can feel free to chime in here. I would recommend probably two of the 1-gallon gatoraid containers fed through a gas separator into your power head if you are going to have that going directly into the water column. this should produce probably 1 bubble or so per second using the yeast formula below. 

This is what I use for each gatoraid container:
2 cups cane sugar
1/2 tsp dry active yeast (not quick rise)
top all of this off with water to the point the bottle starts to taper down at the top. 

First your rinse the gatoraid bottle out with hot water only, empty it and add the sugar. Then fill approx half way with HOT water to dissolve the sugar then fill it most of the way with cold water to cool it to room temp. While this is taking place add the yeast in a small bowl to some tepid water (100 degrees or so) and stir for a couple mins to activate the yeast then add this to the gatoraid container. some people add baking soda to stabilize the reaction, i haven't felt a need for this as it seems to be pretty stable as is. 

as far as your set up goes try to assemble it like the schematic I have attached to this post. The two 1-gallon generator bottles hooked to a T fitting with airline tubing, going into a 20 ounce gas separator and then into the powerhead intake, of course with a check valve somewhere along the line to prevent backflow. 

I would also refer to the DIY co2 stickys in the DIY forum for more pointers that may help you. 

As far as maintaining this system I would change out 1 of the 1gal CO2 generators every 2 weeks or as often as you feel necessary, to maintain steady CO2 concentrations. 


My set up for my 75gallon has 4 1-gallon gatoraid bottles fed through a 300gph powerhead, which goes through a large DIY co2 reactor full of bioballs for 100% dissolution. I alternate changing 2 of the 1-gallon generators every 2 weeks and achieve constant 30-45ppm readings based on PH/KH charts using this setup.


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## redstrat (Apr 3, 2006)

this is a pic of my DIY CO2 generators, you can see the gas separator on the side, its blue. The check valves are on the caps to the 1-gallon bottles all covered in silicone to prevent leaks. You can also see how I have my "T" fittings setup with the tubing to connect them all.

You can also see part of the bottom of my Reactor in the back its the white PVC thing, not that it really helps to see that much of it.

I apologize for the huge pic I just didnt have much time to shrink it more.










for what its worth.


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## fandango (Aug 20, 2006)

Lono said:


> I recently purchased a Hagen CO2 kit.
> I'm starting to question the effectiveness of the ladder defuser.
> I was wondering if anyone thought that my new idea would work.
> 
> ...


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## Lono (Aug 15, 2006)

First draft.
Two hours and it's cranking out the CO2.


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## redstrat (Apr 3, 2006)

Looks good so far, how much CO2 are you getting just out of curriosity??


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## Lono (Aug 15, 2006)

davis.1841 said:


> Looks good so far, how much CO2 are you getting just out of curriosity??


I wish I knew.
The powerhead is pushing out bubbles out almost constantly. now.


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## redstrat (Apr 3, 2006)

can you hear bubbles hitting the impeller like a clock ticking or is it more of a constant stream, you may have a leak if this is the case. The powerhead creates a pretty strong vacume in the co2 line and if you have a leak it will suck in outside air. I have had this problem before so be sure to check for it. another solution is to pull the airline away from the impeller a little and let the bubbles get sucked in from the line instead of sucked out of the line if you knwo what I mean?


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## Lono (Aug 15, 2006)

At the moment I have the line ran throught the bottom of a powerhead attachment. It's nowhere near the input of the powerhead. It's being channeled throught the filter first.


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## redstrat (Apr 3, 2006)

I have experienced the vacuum even using the quick filter, it’s just something to keep in mind, if it seems like you’re getting a ton of bubbles then it might be happening. I have noticed it’s more likely to happen when the foam needs changed because it gets clogged and a vacuum forms. Yours looks pretty clean/new so it shouldn't be too big of a concern. I also realized something else, you don’t have a gas separator/bubble counter which isn't a problem but this would make it so you will be more likely to hear a slow stream of bubbles (without a leak) where in my setup the co2 comes in bursts as the bubbles are formed in the separator so I hear each bubble hit the impeller individually. 

Another way to check for a leak would be during your next yeast solution change empty the bottle and hook it up without any co2 production; if you still hear bubbles you have a leak. It’s worth it to check it no matter what because a leak in DIY a system can severely reduce its effectiveness. 

Hope its all working well for you.


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## Lono (Aug 15, 2006)

I unplugged the tube from the powerhead and the bubbles are just pouring out. It looks like a little over a bubble a second. Is this good?


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## redstrat (Apr 3, 2006)

yeah thats good, my only concern was the powerhead sucking bubbles from a leak in the airline or around the generator, the only way to tell is to try it when there is no yeast solution in the generator, if there are still bubbles then there is a leak because no CO2 would be produced. Its just a concern, your probably fine though... anyway have you noticed any changes yet? Do you plan to get a ph test kit or some method of measuring ph so you know how much co2 your getting? I would recomend a ph and kh test kit, granted test kits normally suck and aren't that accurate, you can still get some idea of whats going on most of the time.


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## Lono (Aug 15, 2006)

I'm seriously thinking now that I putting out way too much co2.
Check it out.

http://www.angelfire.com/wv2/webbuild7/co2.wmv


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## John N. (Dec 11, 2005)

Wow, I don't think that's all CO2...it would be neat if a DIY bottle could produce that much though. 

It seems that it maybe sucking in some air from some place. Check the lines again for any leaks. Also to see how much output your actually producing take the line out and see how many bubbles are coming out.

What you're seeing is just a hurricane of air from somewhere.

-John N.


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## Lono (Aug 15, 2006)

John N. said:


> Wow, I don't think that's all CO2...it would be neat if a DIY bottle could produce that much though.
> 
> It seems that it maybe sucking in some air from some place. Check the lines again for any leaks. Also to see how much output your actually producing take the line out and see how many bubbles are coming out.
> 
> ...


I can hold the tube to the side of the input of the powerhead and it looks exactly the same. The tube is putting out nearly two bubbles a second. The stream of co2 is constant. I ended up attaching it to my bubble ladder until I get the glass diffuser. It's freaking me out.


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## redstrat (Apr 3, 2006)

Yeah that bubble rate is pretty unbelievable. What yeast recipe did you use and what kind of yeast did you use. That looks like a leak, mine did the same thing but it definately wasn't all Co2. If it was all CO2 your fish would probably be floating by now... so its probably safe to say it isn't. or at least isn't really disolving. Just for comparison, I get 2bubbles per second using 4 1gallon yeast generators. When I had only 2 1-gallon generators I was lucky to get 1bubble per second. So I can't imagine that you would get even close to that with only 1, something just doesn't add up. We'll figure it out though. 

That video was a huge help to see whats really going on.


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## Lono (Aug 15, 2006)

My PH went from 7 to 6.4 in 8 hours....I'm thinking it's all co2.
I told my buddy that started me on this planted tank and he couldn't believe that rapid drop. The DIY kit is one that I found on this site posted by John N.


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## Lono (Aug 15, 2006)

http://s31.photobucket.com/albums/c368/gonzo316/?action=view&current=bubbleladder.flv


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## redstrat (Apr 3, 2006)

well I would say if your getting an adequate pH drop and the fish aren't upset, then all is good lets wait and see how long it lasts before it needs replaced... hopefully it will be consistant for at least a week or 2. Keep an eye on that ph its a pretty good indecator of Co2 concentration as you probably know. if its not broke dont fix it lol. but I'd definately be weary of leaks... that still seems like an awful lot of bubbles even considering the ph drop. whats your KH like? I can't speak for all DIY setups but I know with mine as soon as I see the bubbles the PH starts to drop and it really doesn't take very long before it starts to level off where it reaches its max drop. it could be all CO2 though, all I'm trying to say is definatley check for leaks whenever you can, your definately getting co2 dissolved so its working. congrats


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## redstrat (Apr 3, 2006)

just saw your video, dunno how I missed that but did you get that ph drop using the ladder?? if so you can't possibly have a leak because there is no vacuum. anyway I would just be concerned about the longevity of your yeast recipe if your getting that much production from it... the byproduct of the yeast reaction is alcohol and this eventually kills the yeast thats why it stops so the faster it produces it the more alcohol that is produced... anyway like i said before if it works to your liking then what is there to fix.  looks great!


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## Lono (Aug 15, 2006)

davis.1841 said:


> just saw your video, dunno how I missed that but did you get that ph drop using the ladder?? if so you can't possibly have a leak because there is no vacuum. anyway I would just be concerned about the longevity of your yeast recipe if your getting that much production from it... the byproduct of the yeast reaction is alcohol and this eventually kills the yeast thats why it stops so the faster it produces it the more alcohol that is produced... anyway like i said before if it works to your liking then what is there to fix.  looks great!


This is the exact CO2 kit I bulit.
http://www.aquaticplantcentral.com/forumapc/do-it-yourself/14453-diy-co2-guide-with-pictures-recipes.html

I got the drop w/ the Powerhead but I switched to the ladder last night and my PH was unafected in 24 hours. I did a PWC tonight. With a KH of 7 I really think it's insafe for the fish to have such low PH/6.4.


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## Lono (Aug 15, 2006)

davis.1841 said:


> just saw your video, dunno how I missed that but did you get that ph drop using the ladder?? if so you can't possibly have a leak because there is no vacuum. anyway I would just be concerned about the longevity of your yeast recipe if your getting that much production from it... the byproduct of the yeast reaction is alcohol and this eventually kills the yeast thats why it stops so the faster it produces it the more alcohol that is produced... anyway like i said before if it works to your liking then what is there to fix.  looks great!


This is the exact CO2 kit I built.
http://www.aquaticplantcentral.com/forumapc/do-it-yourself/14453-diy-co2-guide-with-pictures-recipes.html

I got the drop w/ the Powerhead but I switched to the ladder last night and my PH was unaffected in 24 hours. I did a PWC tonight. With a KH of 7 I really think it's unsafe for the fish to have such low PH/6.4.

I just realized that I used 1 and 1/4 tsp of yeast. I missread the thing.
It said 1/4-1 teaspoon of yeast. I thought that meant 1 and 1/4.
AHHHHHHH!!!!!!


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## redstrat (Apr 3, 2006)

now it all makes sense lol. I'd wait and see how long that lasts, it could be a good recipe, you'll just go through more yeast. Watch for consistancy, if it maintains this rate for a while then you've got it made. I'm glad to hear it all worked out.


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