Dual venturi DIY External CO2 reactor

milesm

Prolific Poster
Oct 18, 2006
52
0
6
the bleed line is the second of tom's dual venturi design. the line should be rerouted back to the return line, preferably before the pump's impeller. don't really need this, especially if your reactor dissolves most of the co2. it does add mist to the tank. water/co2/other gases will be constantly shot out of that bleed line because the reactor will be under constant pressure.

yes, those lee's air control valves will leak water, as well as those drip irrigation valves ime. i just run the line into my intake without any valves. i positioned my venturi a bit too high, so i would get misting after only a few minutes after turning on co2. now i 'm using about 20 ft of tubing (you can see it in the picture of my post in the "throttling back pump" thread you started), and it seems like half of the co2 is dissolving after making the trip from the reactor to the intake. you can always plug the hole, or to keep your options open, put a check valve on it.
 
Last edited by a moderator:

htram

Junior Poster
Aug 28, 2010
10
0
1
Alright so I've got most of all the pieces needed to build the reactor from Home Depot except for the 3/16" rigid air line (anyone know here I can find this?) but I still have no clue how to set this thing up. I'm running an Aqua Clear 110 hangover filter in a 90 gallon tank and want to run the reactor using a filter pump.

Does anyone have a picture of this setup? Or can clear things up for me a bit?

I'm aware that it's external and that the top two 3/16" rigid lines on the top are for Co2/venturi but am a little lost as to how to hook it up to a powerhead and how to get the water back into the tank?

Thanks
 
Last edited by a moderator:

milesm

Prolific Poster
Oct 18, 2006
52
0
6
htram;54708 said:
Alright so I've got most of all the pieces needed to build the reactor from Home Depot except for the 3/16" rigid air line (anyone know here I can find this?) but I still have no clue how to set this thing up. I'm running an Aqua Clear 110 hangover filter in a 90 gallon tank and want to run the reactor using a filter pump.

Does anyone have a picture of this setup? Or can clear things up for me a bit?

I'm aware that it's external and that the top two 3/16" rigid lines on the top are for Co2/venturi but am a little lost as to how to hook it up to a powerhead and how to get the water back into the tank?

Thanks
you can get the 3/16" rigid tube at most lsf; made by lee

i would use rex grigg's reactor design, with tom barr's dual venturi feature. rex's is designed to sit on the floor, tom's is not. i would also recommend that you use a main body tube longer than 12" (rex recommends 15").

water enters from the top of the reactor and exits through the bottom. use vinyl tubing to connect the powerhead output to the top of the reactor and use another piece of vinyl tubing from the bottom of the reactor to a spray bar (or some such) in your tank. attach your co2 line to the appropriate 3/16" tube; attach airline tubing to your venturi 3/16" tube and attach the other end of the airline to the input of the powerhead, ahead of the impeller.

using tom's dual venturi design will introduce co2 mist into your tank. if you don't like the look, you can eliminate the 3/16" tubes altogether and use rex's method to connect your co2 line from your regulator to the reactor.
 

htram

Junior Poster
Aug 28, 2010
10
0
1
milesm;54740 said:
you can get the 3/16" rigid tube at most lsf; made by lee

i would use rex grigg's reactor design, with tom barr's dual venturi feature. rex's is designed to sit on the floor, tom's is not. i would also recommend that you use a main body tube longer than 12" (rex recommends 15").

water enters from the top of the reactor and exits through the bottom. use vinyl tubing to connect the powerhead output to the top of the reactor and use another piece of vinyl tubing from the bottom of the reactor to a spray bar (or some such) in your tank. attach your co2 line to the appropriate 3/16" tube; attach airline tubing to your venturi 3/16" tube and attach the other end of the airline to the input of the powerhead, ahead of the impeller.

using tom's dual venturi design will introduce co2 mist into your tank. if you don't like the look, you can eliminate the 3/16" tubes altogether and use rex's method to connect your co2 line from your regulator to the reactor.

Hi!

Thanks for the response. Unfortunately I already bought everything and made Tom's design before seeing your post.

I still have a few questions though (About Tom's design and the powerhead I ended up getting)...

1. With Tom's design, can I just lay the reactor on its' side in the cabinet I have under my tank, run 1/2" vinyl tubing down from the powerhead to the reactor and up from the reactor back into the tank? If not, how should Tom's reactor be installed?

2. The powerhead I ended up getting was a RIO 800. I'm not sure if it has the venturi option on it but I will post a pic of the plug that you insert into the powerhead to connect the 1/2" vinyl tubing. If you notice, on the left side, there is a small piece of plastic that juts up from the plug. That piece is shut by another small piece of plastic which I have removed. The guy at the LFS who sold it to me said that I could use that as the "venturi input".

What are your thoughts? Can I run an air line tubing from the reactor's "venturi" output into the plug pictured below?

30c5f2e.gif


Thanks for all your help, I really appreciate it.
 

scottward

Guru Class Expert
Oct 26, 2007
958
10
18
Brisbane, Australia
1. Reactor needs to be upright so that the bubbles are directly rising against the counter-current, and also so they make it out along the venturi line as designed.

2. You could use this venturi nipple, but you would be better of feeding the venturi line into the RIO before the impellor, such that the impellor smashes up the CO2 making a finer mist.
 

htram

Junior Poster
Aug 28, 2010
10
0
1
scottward;54744 said:
1. Reactor needs to be upright so that the bubbles are directly rising against the counter-current, and also so they make it out along the venturi line as designed.

2. You could use this venturi nipple, but you would be better of feeding the venturi line into the RIO before the impellor, such that the impellor smashes up the CO2 making a finer mist.

Okay, think I got it. :)

I've got the reactor setup underneath my tank in an upright position, secured against the center of the cabinet. Lines running down from the powerhead into the reactor, and a line running up from the reactor to the tank. I've also attached the venturi air line to the nipple mentioned above.

No idea how to attach it before the impellor.. i'm not sure my particular powerhead has an option of doing that?
 

scottward

Guru Class Expert
Oct 26, 2007
958
10
18
Brisbane, Australia
Too easy...I just had a look at a picture of the RIO pump that you have. Those slots are the intake for the pump - you should be able to squeeze the end of the venturi line into one of these slots. You will probably then be able to hear a slight noise as the CO2 bubbles make their way into the impellor chamber and get chopped up. If necessary, you could trim one of the slots slightly so that the venturi line can fit snuggly. Be careful not to shove the line too far in though, you don't want it to hit the impellor. I think this will work better than connecting to the nipple on the outlet, the impellor will mince the bubbles up finer.
 

mdwheeler

Junior Poster
Aug 24, 2010
12
0
1
So i've decided to create an overkill version of this reactor.

Setup: 29 gallon planted
Filter: Eheim Classic 2213-37 with prefilter attachment
Lighting: 2 X 30in Current 48 Watt, 2 10k, 2 6700k
Circulation: Hydor Koralia Nano
Pressurized Co2

So I bought a viaaqua 2300 pump (600gph) thinking I was going with a sump setup...then I changed my mind. But I want to use it somehow, so i've decided to 'mod' your reactor using the pump.

There will be two reactors. One will look just like this one, but with a pump inlet hose at the top side, and a pump return 3/4ths way down the pipe. The inlet (at the top) will go to the pump, and through the pump to a second reactor, filled with bio balls, maybe slightly larger but probably about the same size, and the outlet of the second reactor will pump back into the main reactor. The main reactor will be hooked up to the outflow of the eheim filter. Co2 will be injected into the main reactor, not the second.

I believe the pressure from the monster pump won't really cause a problem since the inlet and outlet are on the same pipe, heck It might even help the eheim pump out more filtered water! I'll aslo be placing the outlet slightly angled to create a spinning vortex in the main reactor

Comments? In theory I believe this will max out efficiency since any accumulated co2 towards the top of the main reactor will be sucked and dispersed in the secondary reactor. Its basically a massive venturi.

4995253672_2e813d47dd.png
 
Last edited by a moderator:

Hook_em

Junior Poster
Sep 20, 2010
6
0
1
Austin, TX
Maybe a stupid question/idea, but has anyone found an easy (infallible) way of routing the venturi return line directly into the input hose of a canister filter? I am thinking of constructing the return line in as short of distance of possible, routing the return line to the top of my Eheim, through the hose. I am trying to avoid another thing going in to the tank, but if the idea doesn't work, I can just zip-tie return line to the filter intake.
 

jimmyn

Junior Poster
Dec 19, 2010
6
0
1
Would like to know if there is a reason for the threaded 90 elbow 1/2" barbed in the original or will it be just as effective with a straight hose barb. Thanks
 
Last edited by a moderator:

pianofish

Junior Poster
Apr 20, 2011
26
0
1
I am wanting to use the venturi design reactor combined with rex griggs, in that it will sit flush on the floor and probably be about 20 inches long, but I would like to plumb it up to a eheim 2217 classic canister filter, and I am really bamboozled as to where the venturi line is supposed to go on an eheim canister. Do I need to actually drill into the output hose on my canister. If I do, do this should the venturi line be put before the reactor in the hose, or after the reactor in the hose?
Any help would be greatly appreciated,
Thanks,
Pianofish
 

pdavis41

Lifetime Members
Dec 26, 2010
41
0
6
38
Chicago-land area
The way mine is rigged up is in the hose before the reactor. So between the canister and the reactor. This way the air will be recirculated through the reactor but not be hard on your canisters motor.
 

mStrand87

Junior Poster
May 4, 2011
1
0
1
Hanover, NH
What are the CO2 inlet pressures required to run this reactor? I am part of an engineering team looking to collect CO2 from generator exhaust in a greenhouse. We will be scaling this design up to meet a 750 gallon tank, and we currently have the exhaust backpressure from a modified natural gas generator as the CO2 input. Will the exhaust pressure need to be stepped up in order to successfully run this design?

Also, sorry for any obvious questions, but did you size this reactor based on the CO2 flowrate, or based on the size of the water tank? How does each factor affect the design?

Any further suggestions will be welcome. Feel free to ask more questions about this project, and thanks!

-Matt S.
 
Last edited by a moderator:

Biollante

Lifetime Charter Member
Lifetime Member
Jun 21, 2009
3,210
1
36
Surprise, AZ
I May Not Understand The Question... That Never Stops Me Answering

Hi Matt S.,

I should let the smart folk answer this... :eek:

The CO2 pressure required should be negligible,:confused: the pump (powerhead) does the work.

I used NG CO2 generators to maintain CO2 at 1200-1500 ppm in a greenhouse and used a small air pump to pump the air through glass stones into simplified versions of the CO2 reactor described here to maintain three 160 gallon tubs of aquatic plants.:gw

I hope this helps,:) if not :eek: I am sure smart folk will be by soon.:cool:

Biollante
 

jerrybforl

Lifetime Members
Lifetime Member
Mar 7, 2010
1,034
2
38
40
Miami Beach, FL.
I'm lost lol...I got lost with all the venturi talk and the gas bypass tubing. There where three holes drilled in the beginning of this thread. What were they all used for? I can build a simple reactor but want to build an efficient one! The tank that it will go on is 29gallon. It uses a Marineland C-220. It is rated for 220GPH. Right now I use a glass diffuser but i want to get rid of it. If I have to I will get a pump for the reactor only. I would really like to have it inline with the filter if its possible. Any suggestions is welcome.
 

milesm

Prolific Poster
Oct 18, 2006
52
0
6
all you need are two holes. one for the co2 input and another one for the venturi mod. the picture shows 3 holes and it shows the 2 options for the venturi placement. so drill a hole in the body of the reactor or on the top of the reactor, not both. the venturi should extend down about 2 to 3 inches into the reactor; the higher you place the venturi line, the sooner you'll get recirculation of gases (and mist). as to top or side placement, i think someone posted that the top mounted version is more efficient. i have mine on the top.

the venturi line should be fed back to the pump before the impeller. that will give you the mist. if you don't like mist, eliminate the venturi entirely or attach some sort of valve to control the amount of gases recirculated through the venturi.

as for powering the reactor, i guess you could use the output of your filter, but i don't know where you'd attach the venturi (feeding it to the filter input may not work properly, i don't know i run mine on a dedicated closed loop). i'm pushing 230gph through my reactor.

finally, if you prefer a free standing reactor, use rex griggs' design with tom's venturi mod.
 

anteleon

Junior Poster
Aug 25, 2010
8
0
1
Australia
Hi guys,

thanks for all the input so far,

i was just wondering if someone could point me in the direction to get the plumbing parts for this reactor online, because im having a lot of trouble finding the parts needed locally here in Australia.

I am currently using the Yeast reactor that's featured on this site and was just wanting to upgrade to this reactor using these elusive parts.

i can get the PVC tube no worries of course and the pump im sure i could sort out as well, its just those little plumbing parts i cant find anywhere I've looked,

thanks in advance,

Robert.
 
Last edited by a moderator:

samh

Guru Class Expert
Nov 16, 2010
193
0
16
SE QLD Australia
The plumbing parts can be found at Tradelink plumbing supplies, reece, PHD and swan plumbing suppliers. Use DWV pipe and fittings as they will be cheaper than pressure fittings, Also use green glue as it's rated to be used with drinking water so should be more safe than blue used for drainage. Don't bother getting any primer.

I haven't been able to find any clear pvc anywhere though I'll the guys at the plumbing supplier i'm there all the time picking gear up... being a dirty plumber for a living