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  Topic Review (Newest First)
06-02-2016 07:15 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 06:45 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 03:43 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 11:42 AM
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 12:02 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 05:42 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 04:40 AM
IUnknown Immortal1,
Thanks so much, super helpful. I'll try it out.
04-29-2016 12:10 AM
Immortal1 IUnknown, having built several Cerges reactors I can offer a few bits of info regarding your situation.
Some of the whole house filters have fairly small holes leading into and out of the filter. This ends up causing the poor flow at the tank output. One way of fixing this is to add a regulated bypass to the Cerges reactor.
As for your reactor filling up with air / cO2, this would be an indication of running too many bubbles per second for the amount of water flowing thru the reactor. Not sure why, but it seems if you have a little slower flow rate thru the reactor, it seems to absorb the cO2 faster. For my system I run 5-8 bubbles per second without issue. Anything more than 8 and I start building a bubble in the top of the reactor.

04-28-2016 03:42 AM
IUnknown I have been having issues with my cerges reactor filling up with air, and worried that the flow rate has been reduced too much. Haven't read the whole thread, but does the DIY Griggs style reactor provide more flow? Why is air filling up?
04-11-2016 01:05 AM
Originally Posted by plant_guru View Post
None of the pics in the first post are working

As micca stated above, look at post #770 - all the pics u need are there. Hopefully they stay there for the coming years to help other hobbyists.

I guess that's why these things should be made sickies - or does that not prevent the image source from disappearing I wonder.... [emoji848]
04-10-2016 10:34 PM
plant_guru None of the pics in the first post are working
04-10-2016 05:01 PM
Originally Posted by Patriot View Post
Did you have a sponge in the filter? I had the same problem when the sponge clogged.
Nah, had nothing in then I got to the point where I began taking media out of the the point where it was empty!!! It went from a slow trickle to maybe a medium trickle. Smh.
04-10-2016 04:05 PM
Originally Posted by seandelevan View Post
I ditched the Cerges reactor after 5 years because of lack of flow. It was pitiful. I needed to eheim 2015 at one point. The one connected to the reactor was at best a weak trickle...the one without was full stream. Finally went I with DIY Griggs style reactor and it was good to go.
Did you have a sponge in the filter? I had the same problem when the sponge clogged.
04-10-2016 04:03 PM
seandelevan I ditched the Cerges reactor after 5 years because of lack of flow. It was pitiful. I needed two eheim 2015s at one point. The one connected to the cerges reactor was at best a weak trickle...the one without was full stream. Finally went with a DIY Griggs style reactor and it was good to go. Didn't need two filters taking up space anymore. I would do a cerges again if I had something like a fx5 or fx6 that had over the top flow.
04-03-2016 06:59 AM
Patriot I would get the largest you could possibly fit. The bubbleight not have time to diffuse in such a small space.
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