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  Topic Review (Newest First)
10-02-2016 09:02 PM
Patriot Anyone using this with a Fluval FX6?
10-02-2016 08:47 PM
michu Just realized I was being incredibly rude by asking for help in this thread. I do apologize. I posted a new thread if anyone would like to help.
09-23-2016 03:45 PM
Originally Posted by micca View Post
ah.... thank you micca.
09-23-2016 05:36 AM
Originally Posted by ernest View Post
why the pictures are not shown?
Click here for pictures.
09-22-2016 05:39 PM
plantsrockmysocks The pictures were moved/delete from Craigthor's Photobucket account.
09-22-2016 05:01 PM
Originally Posted by Craigthor View Post
Have to thank our Russian friends for this one. After playing with the Rex Griggs reactor I wanted to try something else. Principal and cost are about the same design is different.

Google Translate

What you will need:

Omni OB1 Series A House Filter
2- 1/2" Male Threaded Adaptors with Barb end
2- 3/4" 90 degree Street fitting
2- 3/4" PVC Male Adaptor
2- 3/4" x 1/2" PVC Bushing
1- 3/4" CPVC Coupling - Note this has to be CPVC not PVC as the PVC fittings are too big
1- 6 3/4" x 3/4" CPVC Pipe - Again has to be CPVC and not PVC
PVC Primer and Cement
CO2 Tubing
Teflon Thread Tape
Needle Nose Pliers
Filter Tubing
Drill and Drill bit for your CO2 Tubing

Total cost as ~ $23 each about the same as the Rex Griggs inline reactor if you don't use clear pvc.

Filter Housing:

Start by removing the Priming Button via the screw on the inside of the lid for the housing:

Drill out the hole to accept your CO2 tubing this hole shpould be smaller then your CO2 Tubing so it creates its' own seal.

Cut the CO2 tubing at a sharp angle so you can stick it through and pull it with the needle nose pliers. This should be slightly tough to pull through as it will create a seal as you pull the tubing through.

Cut the CPVC pipe off at 6 3/4", if you are using a different filter you may have to adjust the cut off length. I cut mine so it was about 3/4" off the bottom. Push the CPVC coupler over the nipple in the lid, should fit really snug. Then push the CPVC pipe into the coupler. I didn't glue this together as it was a snug fit and should be under little pressure.

Lay out and glue the fittings together, with the fitting I chose you won't need any extra 3/4" pipe as all the fittings go together.

Attach the fittings to each side jsut make sure you hook them up according to the Flow marking on the lid. Finished Product.

I will update tomorrow once I install these as to how effective they are, but based on looks they should function really well. According to the article I linked to about he got a .5 PH change in a matter of minutes.

why the pictures are not shown?
08-18-2016 12:30 PM
Originally Posted by snowman1235 View Post
I am reading into the various DIY Cerges CO2 reactors for the 330g tank I am building. I came across this thread, which looks it could be very useful to read from Tom Barr, but all the images seem to be broken links:
How To Build A Cerges CO2 Reactor - Aquarium Plants - Barr Report

Was this design reported also anywhere else by Tom, where images would still be active?
This is the dual venturi build from Tom Barr (modified Rex Grigg design)
Dual venturi DIY External CO2 reactor - Aquarium Plants - Barr Report

The link you posted, the JPG (JPEG) links aren't working for me (maybe you have to be a logged in member? or the OP deleted the pics from their computer), but all the other pictures throughout the thread display for me.

Any way, if you still can't see the pics on your linked page, the Cerges build on that thread is just a typical Cerges build.
08-18-2016 11:30 AM
snowman1235 I am reading into the various DIY Cerges CO2 reactors for the 330g tank I am building. I came across this thread, which looks it could be very useful to read from Tom Barr, but all the images seem to be broken links:
How To Build A Cerges CO2 Reactor - Aquarium Plants - Barr Report

Was this design reported also anywhere else by Tom, where images would still be active?
06-02-2016 08:15 PM
burr740 @WaterLife I know the adjustable water filters with a built in cut off on top, have much smaller holes than the regular ones. I made the mistake of buying one of those first, thinking it would be a good thing, then noticed the holes inside were like 5/16" dia. That's just a guess, but they looked tiny. Had to go buy another one
06-02-2016 07:45 PM
IUnknown Anyone have links from Amazon for a WHF housing? The one I got at lowes has inlet and outlets that look super restrictive and is cutting my flow. This is for a 100 gallon. And a link to the center pipe, I used tubing but the Co2 is eating it. Like a defacto setup that is tried and true.
06-02-2016 04:43 PM
WaterLife Anyone have experience using a SunSun 304/404 with either a Cerges or Griggs reactor in-line and can comment on flow rate reduction? Size of reactor housing (and maybe inlet/outlet diameters) info may be helpful.

What @Immortal1 stated about smaller internal holes on Cerges whole house filter housings makes sense. Anyone have a particular brand of WHF housing that had large holes/didn't reduce much flow?
I assume Griggs style reactors would not have the same issues (small holes significantly reducing flow)

I was thinking of doing a 20" Cerges since I liked the WHF housing appearance better than PVC Griggs, but if flow rate would be reduced much more with the Cerges, or require a by-pass to be made with PVC, then I might just go straight ahead and build a PVC Griggs and avoid the hassle (likely save some dough too).
For the SunSun mentioned above, the Cerges housing should have 3/4" inlet/outlet threads right, not 3/8"?
If I went the Griggs design, I would probably still do at least 20" in length (standing tall). What diameter pipes should be used?
06-02-2016 12:42 PM
N2uqs Hello everyone,

I need advice on a buying a pump for this style of reactor. How many GPH do I want running into it. Tank is 55 gal before substrate, wood and plantings so I'm guessing it's about 45 gal or so. What size Cerges filter should I buy a 10" or 20"? Filter is a small Wet / Dry. Thanks for the advice....
04-30-2016 01:02 AM
Immortal1 Burr, are you asking about 8 bubbles per second at 10 psi cO2 pressure verses 8 bubbles per second at 30 psi cO2 pressure?
If so, then yes, there would be a big difference - if....
and the "if" is the tough part of the discussion to understand for some. I will give it a try. To begin with, assume the amount of water column pressure within the reactor is 10psi. If you set your cO2 regulator at 10psi then there really is not much incentive for the cO2 gas to travel thru the bubble counter and down the tube into the reactor.
If you set your cO2 regulator at 20psi then your cO2 would have an incentive to go into the reactor. Would it be a 10psi incentive? Likely not. The water colume pressure within the reactor will only put up a certian amount of resistance to the inbound cO2 gas. If you were to adjust the cO2 regulator to 30psi then you would assume your getting a lot more cO2 per bubble but again, the small tube from the regulator to the reactor offers very little resistance and the water colume pressure is still only 10psi (assuming for discussion).

Now, if you had a different type if cO2 dispersion method, say an in tank ceramic diffuser then the regulator pressure can make a significant difference. The diffuser is offering much more resistance than an open tube. Lets assume the diffuser requires 25 psi to blow tiny bubbles and at 35psi it blows a lot more tiny bubbles. My guess would be 8 bubbles per second at 35 psi would yield more cO2 dispersed than 8 bubbles per second at 25 psi.

Wow, lot of mumbo jumbo :-)

How about some more. If you mount your Cerges or Griggs reactor in such a way so that the top of the reactor was even with the water level in your tank, then the water column pressure within the reactor would be nearly zero. The incoming water from your canister filter would bounce the cO2 bubbles around a bunch but wound not necessarily "squeeze" the cO2 bubbles into submission. Also, the amount of cO2 pressure within the small open ended tube would be nearly zero psi so the amount of cO2 getting into the reactor would be very small.
If you mounted your reactor in such a way so that the top of the reactor was 10 feet below the water level of your tank there would be a significant amount of water column pressure to "squeeze" the cO2 bubbles into submission! Also, there would be a significantly higher amount of resistance to cO2 gas entering the reactor so you would have to increase your regulator psi which inturn would greatly increase the amount of cO2 gas entering the reactor!

Pretty sure non of us would like to mount our tanks 10' in the air. But, for those who have the display tank mounted on the first floor and the sump / filter equipment setup in the basement - I would guess you could dump a lot of cO2 into the water column!

As for the rest of us with normal setups, I would like to propose an interesting question. Which would be better, a 30" tall Griggs reactor made out of 2" PVC and mounted vertically under the tank? Or a 10" tall Griggs reactor made out of 6" PVC mounted vertically with the bottom of the reactor mounted a low as possible?

Ok, too much thinking. Time for a beer.
04-29-2016 06:42 AM
Originally Posted by Immortal1 View Post
Yes, with the bypass fully open, water still runs thru the reactor. How much exactly, I don't now. Will have to spend some time figuring out what regulator pressure, what BPS, what bypass valve setting works. Should be fun.
Hey Immortal,

Would there be any difference between 8 bps going in at 10 psi wp and 8 bps going in at 30?

Still fine tuning my griggs and just wondering. On one hand seems like there would be no difference, but on the other hand seems like there might be.
04-29-2016 05:40 AM
IUnknown Immortal1,
Thanks so much, super helpful. I'll try it out.
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