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ADA CO2 Diffuser

Contents:

  1. ADA CO2 disperser
    by khewss/singnet.com.sg (Khew Sin Sun) (Tue, 24 Mar 1998)
  2. Dupla Delta CO2 system query
    by David Aiken <d.aiken/eis.net.au> (Mon, 23 Mar 1998)
  3. ADA CO2 disperser
    by David Aiken <d.aiken/eis.net.au> (Fri, 20 Mar 1998)
  4. ADA CO2 disperser
    by Neil Frank <nfrank/mindspring.com> (Fri, 20 Mar 1998)
  5. Aquatic Plants Digest V3 #707
    by Dave Gomberg <gomberg/wcf.com> (Mon, 14 Dec 1998)
  6. Aquatic Plants Digest V3 #710
    by Dave Gomberg <gomberg/wcf.com> (Tue, 15 Dec 1998)
  7. A Better CO2 reactor
    by "Beard, Kelly" <KBeard/comdata.com> (Fri, 29 Jan 1999)
  8. Eheim pressure
    by Dave Gomberg <gomberg/wcf.com> (Sat, 30 Jan 1999)
  9. A Better CO2 reactor
    by krandall/world.std.com (Fri, 29 Jan 1999)
  10. Aquatic Plants Digest V3 #813
    by KianLee_Lim/singaporeair.com.sg (Mon, 1 Feb 1999)
  11. RE: High Pressure vs Low Pressure CO2 systems
    by "James Purchase" <jpurch/interlog.com> (Wed, 3 Feb 1999)
  12. Eheim Diffuser
    by Sherlock Wong <wong/dt.wdc.com> (Fri, 26 Mar 1999)
  13. CO2
    by "Dixon, Steven T. (Exchange)" <stdixon/ben.bechtel.com> (Mon, 10 May 1999)
  14. Eheim diffusors
    by Dave Gomberg <gomberg/wcf.com> (Wed, 22 Sep 1999)
  15. RE:CO2 reactors
    by "Thomas Barr" <tcbiii/earthlink.net> (Sat, 13 May 2000)
  16. Re:clogged CO2 diffusers
    by Ron Barter <mistnfrost/superaje.com> (Tue, 16 Jan 2001)
  17. CO2 injection line-ups (was Aquatic plants blah we know already blah)
    by ikallio/innoveda.com (Ilkka Kallio) (Thu, 1 Feb 2001)
  18. CO2 injection line-ups (was Aquatic plants blah we know already blah)
    by Wright Huntley <huntley1/home.com> (Thu, 01 Feb 2001)
  19. ada CO2 diffuser
    by Michael Moore <miketmoore/yahoo.com> (Fri, 20 Apr 2001)
  20. Needle Valves in CO2 Systems Poll
    by "Dixon, Steven T. (BEn)" <stdixon/ben.bechtel.com> (Thu, 4 Jan 2001)
  21. Needle valves in CO2 systems poll & ?
    by Jay Reeves <jbreeves/isd.net> (Thu, 04 Jan 2001)
  22. Reactors vs diffusors
    by Erik Olson <erik/thekrib.com> (Sun, 28 Jan 2001)
  23. Aquatic Plants Digest V4 #809
    by Chris Schmelzer <chris/coffeecafes.com> (Tue, 30 Jan 2001)
  24. Eheim diffusor clogging
    by Dave Gomberg <gomberg/wcf.com> (Wed, 20 Jun 2001)
  25. re: CO2 FAQ
    by Erik Olson <erik/thekrib.com> (Wed, 20 Sep 2000)

ADA CO2 disperser

by khewss/singnet.com.sg (Khew Sin Sun)
Date: Tue, 24 Mar 1998
To: APD

>Date: Fri, 20 Mar 1998 19:13:20 +1000
>From: David Aiken <d.aiken-at-eis.net.au>
>Subject: Re: ADA CO2 disperser
>
>Roxanne Bittman asked:
>>
>>Has anyone had experience with the ADA glass "pollen" CO2 disperser?  I=
t
>looks
>>intriguing.
>>

I'm using two of the ADA Pollen 50 diffusers for my 200 gal. tank. It
doesn't have any safety valves built into it as u have observed so u'd ne=
ed
to hook up some one way check valve. ADA's check valve,the Rubicon,is thi=
s
"made of glass" device which has a little red glass ball inside which sto=
ps
back flow. Real thing of beauty (typical ADA!!) but one heck of an
expensive (typical ADA too!! ) ;-)

Khew


Dupla Delta CO2 system query

by David Aiken <d.aiken/eis.net.au>
Date: Mon, 23 Mar 1998

On 23/3/98, "icom" <icom-at-dynamo.com.ar> wrote:

>	That's because I just bought a used german
>Dupla CO2 system, (I think the model is Delta)

The Delta is the cheapest Dupla system with a little ceramic diffuser =

outlet for the CO2 rather than a reactor.

>I have two questions: in the box, there is a label with the =

>following words:"Do not operate or store in sleeping rooms"
>Anything to say? I don't have other rooms!

No comments apart from the obvious that they are concerned about =

asphyxiation whilst people sleep. =


>Second question: I don't have the instruction manuals.. do you
>know how the bubbles/minute/galon relation is?

The directions are pretty scanty in the manual anyway. Basically they say=
 =

the following (modified to accommodate the lack of diagrams here):

- - close both valves - the big one on the top of the CO2 bottle and the =

small one on the brass fitting;

- - open the big one on the bottle by a half turn;

- - open the valve of the fitting. Watch the bubbles in the bottom of the=
 =

diffuser and adjsut to approx 20 bubbles a minute. Note that the number =

of bubbles takes some time to change so allow a few minutes between =

adjustments to wait and see what happens when you're setting the rate.

What they don't say is that you will need to play around with the flow =

rate to suit your needs - the 20 bubbles a minute is a starting figure. =

Use the CO2 indicator that comes with the set to get the flow rate right.=


David Aiken

ADA CO2 disperser

by David Aiken <d.aiken/eis.net.au>
Date: Fri, 20 Mar 1998
To: ADA

Roxanne Bittman asked:
>
>Has anyone had experience with the ADA glass "pollen" CO2 disperser?  It 
looks 
>intriguing.
>
I haven't had any experience with it but, from the photos, it looks like 
it may work in the same manner as the small Dupla disperser which uses a 
sintered glass plate to diffuse the CO2 into fine bubbles. I've been 
using the Dupla device for around 2 years quite successfully.

I have to admit that the ADA device looks nicer, but it doesn't seem to 
have the spring-loaded valve at the base that the Dupla device has to 
prevent water flowing back down the line to the gas bottle, which I 
understand can happen under some circumstances. Perhaps they have some 
form of protection built into their valve/regulator set-up. or perhaps 
it's totally unnecessary.

David Aiken


ADA CO2 disperser

by Neil Frank <nfrank/mindspring.com>
Date: Fri, 20 Mar 1998

>>Has anyone had experience with the ADA glass "pollen" CO2 disperser?  It
looks 
>>intriguing.
>>
>>Roxanne Bittman
>>

I have been using the "Pollen Glass CO2 distributor" for almost 4 years on
one tank. I really like it.... much more compact and unobstrusive than many
other commercial or home made diffusers. It injects an extremely fine mist
of CO2 bubbles thru a ceramic disc. Because of the high solubility of CO2,
and my injection depth (~1 foot or 30cm), I suspect that by the time the
mist is half way towards the surface, the CO2 has already dissolved and the
residual bubbles are only N2 or O2 from the water. There is a powerhead
immediately above to ensure good circulation within the tank.

I got the CO2 distributor intended for a 70 gal tank (disc diam = ~2-3cm),
but have it in a 125g (500L). It is connected to a pH controller and has no
trouble keeping up (sorry... can't give you equivalent bubble count). The
only drawback is that it must be occassionally cleaned to clear the disc of
algae or other coating that restricts the CO2. You can see when this this
is needed when the mist only comes out of part of the disc. Every 6 months
or so, I soak it with dilute chlorox... there is also an ADA product
intended for this purpose. A certain amount of CO2 pressure is needed to
get thru the disc... although it works well with a CO2 tank, I wouldn't
recommend it with a pop bottle reactor.



Aquatic Plants Digest V3 #707

by Dave Gomberg <gomberg/wcf.com>
Date: Mon, 14 Dec 1998

At 12:13 PM 12/14/98 -0500, James Purchase described his plan: 
>
>
>Proposed Setup to provide Multiple Aquariums with an Equal Amount of CO2:
[big snip]

Good plan, but if you use Eheim reactors (diffusors) you can ditch the
bubble counters and the check valves  and the needle valve.  That was what
I was trying to say earlier.  All you need is the 4 t valves and 4 Eheims.
The t valves let you balance any slight production variations in the Eheims.

- --
Dave Gomberg, San Francisco            mailto:gomberg@wcf.com
http://www.wcf.com/wcf
- -----------------------------------------------------------------



Aquatic Plants Digest V3 #710

by Dave Gomberg <gomberg/wcf.com>
Date: Tue, 15 Dec 1998

At 03:48 AM 12/15/98 -0500, James Purchase asked:
>Dave Gomberg wrote:
>
>> Good plan, but if you use Eheim reactors (diffusors) you can ditch the
>> bubble counters and the check valves  and the needle valve.  That was what
>> I was trying to say earlier.  All you need is the 4 t valves and 4 Eheims.
>> The t valves let you balance any slight production variations in
>> the Eheims.
>So, Dave, you are saying that I just need:
>Regulator - T-Valve Manifold with 4 output points, each attached to an Eheim
>diffusor. No Needle Valves. I assume you would also include a check valve to
>protect the regulator from backflow?

No check valves or bubble counters needed, Eheims have both.  Your parts
list is correct.  If you need Eheims, see the CO2 page in my sig.

- --
Dave Gomberg, San Francisco            mailto:gomberg@wcf.com
http://www.wcf.com/wcf
- -----------------------------------------------------------------



A Better CO2 reactor

by "Beard, Kelly" <KBeard/comdata.com>
Date: Fri, 29 Jan 1999

I've got an Eheim diffuser.  It's okay, but a lot of those little bubbles
make it to the surface, so that's wasted CO2.  I was looking at maybe one of
the Dupla reactors, or at least something that might fully incorporate CO2
into the water, so the only bubbles you see in your tank is the ones your
plants produce.

Anyone have a recommendation they are sold on?


Kelly Beard, Cat IV, Team Allanti
President, Allanti Cycling Club - http://www.allanti.com 
IBM Global Services

The following will apply to any Year 2000 statements included in this
e-mail:  This is a Year 2000 Readiness Disclosure and Year 2000 Statement
under the Year 2000 Information and Readiness Disclosure Act.  Any
statements made in this document regarding non-IBM products are
republications; such statements are based on information provided by the
applicable third party and have not been independently verified by IBM.


Eheim pressure

by Dave Gomberg <gomberg/wcf.com>
Date: Sat, 30 Jan 1999

At 03:48 PM 1/30/99 -0500, >> James Purchase wrote:
>> [Eheim diffusors]  will  NOT work with Yeast Method CO2. 
>>You definately need to use compressed  CO2 in order to
>> achieve the pressure needed to drive the CO2 through the
>> ceramic  plates.
>Could you give us an estimate of how many PSI are required? 

Speaking specifically for the Eheim only, about 8-10psi are required for
bubbling to begin.  At 20psi you get pretty much full volume.  About
14-16psi is the usual operating range, depending on tank size, light level,
etc.

- --
Dave Gomberg, San Francisco            mailto:gomberg@wcf.com
http://www.wcf.com/co2iron
- -----------------------------------------------------------------


A Better CO2 reactor

by krandall/world.std.com
Date: Fri, 29 Jan 1999

Kelly Beard wrote:

>I've got an Eheim diffuser.  It's okay, but a lot of those little bubbles
>make it to the surface, so that's wasted CO2.  I was looking at maybe one of
>the Dupla reactors, or at least something that might fully incorporate CO2
>into the water, so the only bubbles you see in your tank is the ones your
>plants produce.
>
>Anyone have a recommendation they are sold on?

I've got one too, and like you, I'd prefer not to waste any CO2.  I attach
a gravel vac or clear spring water bottle with the bottom cut off to the
outflow of my canisters.  Even large single bubbles out of airline tubing
can be dissolved in this way, but then you need a needle valve to regulate
the flow.  The Eheim diffuser can simply be placed below this instead.  The
water current flowing down as the fine mist of bubbles go up dissolves them
with no problem.

Even without though, if you place the diffuser low enough in the tank, you
don't lose much of any.  Look how much smaller the bubbles are by the time
they reach the water surface.  They're mostly gone.


Karen Randall
Aquatic Gardeners Association


Aquatic Plants Digest V3 #813

by KianLee_Lim/singaporeair.com.sg
Date: Mon, 1 Feb 1999

Hi to everyone,
     I read with interest about the issue of CO2 escaping into the
atmosphere when using the  ceramic disc type of diffuser. I believe that if
you position your diffuser near to the substrate, the CO2 will take longer
to reach the surface of the water,thus allowing the fine CO2 bubbles more
time to react with the water, no doubt there will still be bubbles reaching
the surface of the water,but I think the content will not be CO2 already.
Anyway, has anybody ever check  the concentration of CO2 of the bubble when
they reach the surface of the water .

##   It is going to be Chinese Lunar New Year  ##




>
> Date: Fri, 29 Jan 1999 10:51:12 -0600
> From: "Beard, Kelly" <KBeard@comdata.com>
> Subject: A Better CO2 reactor
>
> I've got an Eheim diffuser.  It's okay, but a lot of those little bubbles
> make it to the surface, so that's wasted CO2.

Snip...

I keep hearing this (and about surface turbulence, etc.) losing CO2. For
the life of me, I don't understand the logic behind this thinking.

When I inject CO2, I just use fine airstones, and let some of the
bubbles reach the surface. If your tank is properly covered, the heavier
CO2 just accumulates inside the hood and gets dissolved into the water
from there. Surface agitation or motion just *helps*. CO2 is *really*
soluble in water. Very little is lost.

I wouldn't even try to inject CO2 into an open-topped tank, so maybe
that's what I am missing.


RE: High Pressure vs Low Pressure CO2 systems

by "James Purchase" <jpurch/interlog.com>
Date: Wed, 3 Feb 1999

Dave Gomberg recently (and very kindly) answered a question I had. As luck
would have it, that only leads to more questions...

>And why, if this is the
>proper way to set up a "low pressure" system, does EVERY commercial
>manufacturer who sells purpose designed CO2 devices recommend the
>regulator-needle-valve combination?

[Because they are trying to push their own appliance.   The only company
[that sells a complete system (that I know of) and uses a high-pressure
[appliance is ADA.  So his design is fine.   Everyone is trying to use a
[needle valve when they really need a second regulator.   They do this
[because it is cheaper and simpler.  But it is also unstable unless you use
[a very very expensive needle valve (the Hoke, made in England, would be my
[choice if I insisted on low pressure via a needle valve).  A Hoke costs
[about $100 tho.

I've located Hoke's website and they do list a number of needle valves, but
they all seem to be rated of extremely high pressures - which Hoke Needle
Valve would you recommend?

[To summarize, low pressure systems seem to make more sense until you look
[at the details of how you are going to build your system.   But they are
[hard to build so they are stable.   If you like a stable system, high
[pressure systems are so much easier to build that is worth restricting
[yourself to the four or so high pressure appliances available (Dupla, ADA,
[Eheim, Point Four).  Of these the Eheim is the clear preference for
[price/performance.

Christopher Coleman ran some comparison tests on th Eheim diffuser vs. the
ADA Pollen Glass diffuser and posted the results a while ago. He seemed to
agree that the Eheim won out on price/performance but did note that the ADA
unit was more efficient. I have an Eheim diffuser and a Dupla Atomizer and
the biggest difference I can see (other than the fact that the Eheim forces
you to use "micro tubing") is that in the Eheim unit, the diffusion plate is
held within the rubber "O-ring" gasket, while in the Dupla Atomizer the
actual disk is larger and there are "O-ring" gaskets both above it and below
it. Another poster mentioned that he has possibly experienced some leakage
of CO2 between the disk and the gasket (it's only a friction fit), producing
larger bubbles than if all of the CO2 was being forced through the ceramic
disk. I haven't had the opportunity to actually get these things wet yet, so
I can't say for certain if this is the case, but I suspect that the physical
design of the Dupla unit is superior to the Eheim (due to the dual "O-rings"
and the decreased likely hood of leakage). And that has nothing whatsoever
to do with any bias on my part for "Dulpa" equipment.

I checked out Point Four's website (yeah! another Canadian firm!!!) and
their devices look interesting (http://www.pointfour.com/diffuser.htm). One
of the things which people complain about using diffusion devices as well as
power heads to break up CO2, is the fine mist of bubbles which "clouds" the
water column in the tank. The Point Four diffuser looks like it could be a
major offender in this regard (due to it's large size and obvious
efficiency, if the photo on the website is accurate) but I could imagine
constructing an in-tank reactor for one of these where water was introduced
at the top and the diffuser was located close to the bottom, where the water
would exit (counter-current design). The fine mist of CO2 would rise against
the downward flow of water and pick up CO2 on its way.

Gosh, it seems like there is no end to the gadgets...

James Purchase
Toronto


Eheim Diffuser

by Sherlock Wong <wong/dt.wdc.com>
Date: Fri, 26 Mar 1999

I recently setup a Eheim high pressure diffuser.
Lots of bubbles were escaping to the surface, so
I put the diffuser below the intake of my canister
filter. Only a stray bubble now and then escapes
to the surface. The return filtered water is free of
bubbles. Some CO2 does collect in the canister filter,
rocking the filter expels the built up CO2.

The Eheim can also be partially buried under gravel
to lower it (bury the tubing part).

I'm also hoping that this will also prevent sludge/algae
from building up in the diffuser, because the intake
strainer blocks light from getting to the sintered
glass in the diffuser.

Sherlock Wong


CO2

by "Dixon, Steven T. (Exchange)" <stdixon/ben.bechtel.com>
Date: Mon, 10 May 1999

Dave G. wrote in justification of criticism of low pressure systems:
"Here is the sad part.   If your input pressure is 5psi (go below this
and you risk serious instability problems) and your output is 1.5 psi
(36" of water) and your temperature is 70F, then the Cv you need is
.000007 for one liter per day.   If you want one 2mm bubble of CO2 per
second, that is about 4mm3/sec or 15cm3/hour or .4L/day or a Cv of about
.000003 That is a long way from .004, or the Hoke value of .0008 which
still doesn't hack it."

Here's what's wrong with what Dave is saying, even assuming his calcs
are 100% correct:  There is no reason on earth to run your input
pressure to the metering valve at 5 psi.  I run my Nupro input pressure
at 40 psi and as I said in my last note, Dave could set his watch by my
bubble rate!  <G> A 10# CO2 bottle has lasted over 1 year on my 40
gallon setup.  

BTW, on all of my trips to Dave's house his CO2 levels were over 100 ppm
in his 55 gallon tank!  On the first visit the level was over 200 ppm!
I'm not entirely sure if this is intentional on Dave's part (to a
certain extent I think it is), but it leaves me a little worried that
using just a regulator and Eheim disk without any metering valve is
difficult to control.

I also use the high pressure system that Dave recommends in one of my
tanks (but with a metering valve) and I am quite happy with that setup
as well.  But there is nothing wrong or particularly difficult about
making a low pressure system work quite well either.  Just don't follow
Dave's straw man advice re the input pressure to the metering valve.
It's a problem you don't need to solve.

Steve Dixon in San Francisco


Eheim diffusors

by Dave Gomberg <gomberg/wcf.com>
Date: Wed, 22 Sep 1999

At 03:48 PM 9/22/1999 -0400,  Erik Olson wrote:
>One note on the diffuser: using it renders the expensive needle valve
>useless; it provides a similar role directly, by regulating flow.  Many
>just hook them up directly to the output of their regulator and drive it
>at 13-15 PSI.  I personally had a very bad experience with one, where it
>somehow dumped the entire contents of a 15 pound cylinder into the
>aquarium over a few hours, and killed off my fish.  Dave told me this is a
>normal thing when they're first broken in, but there's no way you'll catch
>me with one on my good aquariums.

Erik is right, when you first break the seal on the check valve, the seal
has been pushed into its seat for the months since it was made and has
molded itself to the shape of the seat.   Over the next few hours it
"unmolds" itself back into a more normal shape.   This will change the flow
characteristics of the diffusor.   Sadly, in Eric's case, he was not around
to observe this and ended up dumping a whole tank of CO2 (which is always a
bad idea).  I would recommend keeping a close eye on any new system the
first few days you have it hooked up.  I don't know of any that don't
require some fiddling until they are just right.   
- --
Dave Gomberg, San Francisco            mailto:gomberg@wcf.com
For low cost CO2 systems that work:  http://www.wcf.com/co2iron 
Tropica MasterGrow in the USA:      http://www.wcf.com/tropica 
- -----------------------------------------------------------------


RE:CO2 reactors

by "Thomas Barr" <tcbiii/earthlink.net>
Date: Sat, 13 May 2000

>Tom writes:
>
>You don't get as much clogging but you also can't see if it's clogged
>either. I prefer the maintenance that I can see and figure out what's wrong
>at a glance.
>
>I reply:
>
>I tried it with clear tubing but it just didn't work. I think that since the
>header is located inside the tank and is fully exposed to the lights the
>algae grew very quickly and clogged the garden hose rings within a few
>weeks. I would then have to take the thing apart and try and clean the
>rings. With opaque tubing there is no maintainance at all so far except for
>rinsing the sponge every few weeks which is a much easier job.
>
Ever tried placing it down further inside your tank? Like the bottom back
where it's very dark(Typically the darkest)? This is the best place to place
the diffusers- HP disc-LP reactors etc as the output trickles up through the
plants, gives the CO2 the most contact time with the plants, can provide
gentle even current at the bottom, rising up through the plants, keeps all
CO2  equipment cleaner being a very dark spot in your tank and keeps the
stuff out of sight except from the side but you can change this also. If the
opaque stuff is easier, by all means keep it. Prefiltering the reactors can
be important depending on design/detritus levels. 
Can you place the header outside the tank? A simple long hose about 4 ft
long hanging all rolled up off the backside of the tank works well too. I
direct the output with a spray bar along the bottom(see above). 
Regards, 
Tom Barr


  


Re:clogged CO2 diffusers

by Ron Barter <mistnfrost/superaje.com>
Date: Tue, 16 Jan 2001

Hi Raj,

    I've used the ceramic disc cleaner sold by M3 in the states, but even
after soaking overnight, the algae buildup was still not cleaned off, even
after scrubbing with a toothbrush. Finally I put the disc in a small dish of
laundry bleach; is was snow white and clear after less than 10 minutes.

    I have no idea what is in the cleaner that M3 sells, as I could see no
contents written on the package, just some rather amusing english
translations for its use ("keep reaching out of the children"). Next time
I'll be tempted to just try the bleach first. After bleaching, be sure to
soak it in fresh water well before putting it back in a tank.

Best regards,

Ron Barter,
Perth, Ontario
- ------------------ 
> Date: Tue, 16 Jan 2001 11:58:07 +0530
> From: Raj <ggrk@blr.vsnl.net.in>
> Subject: Clogged CO2 diffusers
> 
> My ceramic CO2 diffusers seem to be clogged.
> 
> How do I clear clogged diffusers?
> 
> - --
> Raj, vu2zap
> Bangalore, South India
> http://members.xoom.com/ggrk/


CO2 injection line-ups (was Aquatic plants blah we know already blah)

by ikallio/innoveda.com (Ilkka Kallio)
Date: Thu, 1 Feb 2001

On Wed, 31 Jan 2001, Stephen Boulet wrote:
>> How about adding another possibility:
>> 
>> Bottle + Reg + Needle Valve + Glass diffuser
>> - - -----------------------------
>> PRO simple, not intrusive in tank, self-contained
>> CON none known   ;)

On 1 Feb 2001 Erik Olson replied:
> Having tried this myself, I can state:
>
> CON injection rate still not particularly adjustable, and still not super
> efficient.  And because of the double flow restriction (needle +
> diffusor), I found it's difficult to make adjustments to the needle valve
> once the diffuser is installed (the feedback takes on the order of an
> hour). It's better than NOT having the needle valve, but still not as good
> as using a true reactor system downline.

At first I was having the same difficulty. When you have a 
length of tubing after the regulator/needle valve and 
before the glass diffuser, this tubing operates as storage 
balloon. When you're making an adjustment to reduce the 
flow, it takes a long time for the stored gas to exit from this 
balloon through the diffuser and only after that you can see what 
the new flow rate is. What you need to do is let all the gas 
out of this balloon after each adjustment. I just have a 
connector piece after the regulator/needle valve that I 
can yank apart and vent the extra pressure from the tubing 
whenever I've made an adjustment to the regulator or needle 
valve. Doing this lets me do all the adjusting I need in just 
a couple of minutes.

- -Ilkka

- --------------------------------------
Mr.  I L K K A   K A L L I O
San Jose, CA


CO2 injection line-ups (was Aquatic plants blah we know already blah)

by Wright Huntley <huntley1/home.com>
Date: Thu, 01 Feb 2001

> Date: Thu, 1 Feb 2001 06:25:39 -0800 (PST)
> From: Erik Olson <erik@thekrib.com>
> Subject: Re: CO2 injection line-ups (was Aquatic plants blah we know already blah)
> 
> On Wed, 31 Jan 2001, Stephen Boulet wrote:
> 
> > How about adding another possibility:
> > 
> > Bottle + Reg + Needle Valve + Glass diffuser
> > - - -----------------------------
> > PRO simple, not intrusive in tank, self-contained
> > CON none known   ;)
> 
> Having tried this myself, I can state:
> 
> CON injection rate still not particularly adjustable, and still not super
> efficient.  And because of the double flow restriction (needle +
> diffusor), I found it's difficult to make adjustments to the needle valve
> once the diffuser is installed (the feedback takes on the order of an
> hour). It's better than NOT having the needle valve, but still not as good
> as using a true reactor system downline.
>
 
This sounds like you did not remove the check valve that comes with the
Eheim diffuser. That's where the pressure drop and squirrely performance
come from, not from the sintered glass diffuser, itself.

This point seems to have been missed a great deal in these discussions. The
diffuser is great, but the 12-15 psi across the check valve, required to
open it, gives a huge reservoir of pressurized gas between the needle valve
(and regulator), and the diffuser. You can shut the valve clear off, and the
bubbles will continue for quite a long while.

Getting rid of the check valve (which isn't needed for anything) will make
the system much easier to adjust. The only pressure in the line from the
needle valve to the diffuser will be a psi or two to overcome water depth.
[The diffuser has almost no pressure drop, by comparison, at our typical
flow rates.]

Where is it written that we must retain a clearly annoying gadget, like that
high-pressure Eheim check valve?

Wright

PS. On efficiency, I see bubbles that almost disappear as they reach the
surface, so most of my gas *is* dissolving on the way up. Since I keep
killies, there is no such thing as an uncovered tank around here. Any
reaching the surface just enriches the CO2 in *that* closed atmosphere, so
probably reaches a high equilibrium, easily. My limited KH and pH tests tell
me it is pretty darned efficient.

- -- 
Wright Huntley, Fremont CA, USA, 510 494-8679  huntleyone at home dot com

                  Paranoids of the world arise!
                You have nothing to lose but your...
               Oh, NO! They are out to get those too?

              *** http://www.libertarian.org/ ***


ada CO2 diffuser

by Michael Moore <miketmoore/yahoo.com>
Date: Fri, 20 Apr 2001
To: erik/thekrib.com

I have seen the ADA diffuser and many diffusers.  
I have also been using for about 15 years now a very easy way of
diffusing co2 into water.  I use something like the dupla  which uses a

sintered glass plate to diffuse.

What I use is available from many laboratory glassware suppliers. 
for example Fisher scientific is a good one!

for ADA you can pay twice or three times as much and the same as dupla.
What you need to look for is funnels,  "Clear Glass buckner Filter
funnels"
they range in size from very very very small to very very very very
big.
I use very very small it is great and all you need is a check valve
that you need to replace about every 4 months.  because the water and
C02 breaks it down.
you might also have some luck if you go to your local university or
college and ask the Chemistry department or Biology department if you
can purchase or have one they really don't use them that much and for
cleaning  concentrated bleach soak and boiling for about 1 hour could
clean chemicals away any question just E-mail me.

by the way if buy one, you will pay about  $15-25 


=====

"Those who are successful work harder!!!!"  

                                       -Howie Long-


__________________________________________________
http://auctions.yahoo.com/


Needle Valves in CO2 Systems Poll

by "Dixon, Steven T. (BEn)" <stdixon/ben.bechtel.com>
Date: Thu, 4 Jan 2001

I've kind of enjoyed the CO2 poll my self-so I guess I ought to throw my
info into the hopper.

1)Describe your CO2 setup
I have two systems, one low pressure and one using Eheim diffusers (I guess
some would call that high pressure).
System A:  An old Sandpoint CO2 system with a Dupla CO2 reactor (the small
one for up to 100 gallons) with a 10# CO2 cylinder.  The Sandpoint appears
to be a no-regulator system.  As best I can tell, a fine metering valve is
simply hooked directly to the CO2 bottle.  The unit included a solenoid
which I leave on 24/7 (because I'm not interested in using a controller).
System B:  Victor 253D regulator (single stage; two gauges) with Nupro M
Series metering valve followed by two Eheim diffusers (better diffusion is a
large tank).  I use a 20# bottle for this setup.  Output pressure of the
regulator is set to 40 psi.

2)How long have you been using this setup?
Sys. A:  5 years
Sys. B:  3 years

3)Have you experienced any problems with this setup?
Sys. A:  None that I've noticed.  I have run the CO2 cylinder empty numerous
times without killing any fish or noticing any gasping or other ill effects.
I do not keep a pH monitor running on this tank-so I don't really know if
there is any dumping as the cylinder runs out of gas, but I don't think
there is much, if any.
Sys. B:  I have run this system empty twice since the CO2 dumping hooray
kicked up on the APD and monitored things closely.  I was surprised by the
results.  In both cases significant dumping occurred even with the use of
the metering valve.  As the pressure in the CO2 cylinder dropped below 800
psi, the output pressure of the regulator slowly increased to ~50 psi (this
is the amount Dave predicted based on his review of the specs of the 253D
regulator which is reported to be one of Victor's better single stage
regulators and not much of a dumper).  At 50 psi the Eheims clearly showed
more gas bubbling into the aquarium.  The pH (Pinpoint with new probe;
calibrated and run continuously) dropped from ~7.0 to ~6.0 over the course
of a couple of days as the output pressure rose.  At KH 5 this represents an
increase in water column CO2 from ~15 ppm to over 100 ppm.  In both cases I
stopped the experiment at this point and reduced the output pressure on the
regulator to 40 psi which restored the pH to ~7.0.  In neither case did any
fish die or exhibit gasping at the surface.

4)If you could change something(s) with your setup, what would it be?
Sys. A:  Nothing.  In fact I'm now quite intrigued by the idea of buying a
good metering valve and hooking it directly to the CO2 bottle (as Sandpoint
apparently decided to do a long time ago).  If I end up dying to know how
much CO2 is left in the bottle, I could always set the cylinder on scale of
some sort and simply weigh it.
Sys. B:  Metering valve setups do dump (notwithstanding a few reports to the
contrary), but perhaps not as badly as systems without need metering valves.
The valves provide some protection IMHO, and are worth the investment.
However, I would like to see the dumping problem solved.  (I think Dave is
close, but the APD flame war has dried up his CO2 business and once he does
have it solved, folks may not have confidence in the solution due to the
noise level of the discussion.)  We need either a regulator that doesn't
dump much or a control system after the regulator which solves the problem.
Dave (with Wright's advice) is working on a new angle.  There may be some
metering valves which create sufficient turbulence/perturbation through high
speed flow rates within the valve to effectively limit dumping.  That would
be a nice turn of events if it pans out.

5)What bubble rate and psi settings do you use?
Sys. A:  one large bubble every 6 seconds, like clockwork, month in month
out.
Sys. B:  don't know (I use the pH to adjust the CO2 level); 40 psi on the
regulator output.

Regards, Steve Dixon in San Francisco


Needle valves in CO2 systems poll & ?

by Jay Reeves <jbreeves/isd.net>
Date: Thu, 04 Jan 2001

1)Describe your CO2 setup.
    I have a Dave Gomberg system.

2)What valve do you use (company name, part number, etc.)?
Aquarium Landscapes EQNV needle valve that I purchased after reading
postings on this digest.  As far as I am concerned the needle valve is
must for this system and in my application.  The CO2 and lighting wiring
are in a closet behind the aquarium, but accessed from a different room
(10 steps aquarium to closet).   However, without the needle valve I was
running between the closet and the tank trying to get it adjusted.  The
needle valve is mounted on a light weight angle bracket behind the
aquarium so I can adjust it with one hand while watching the flow rate -
this feature alone is worth the price of the valve in my application.
The output pressure on the tank is set at 9psi  with a bubble rate of
about 3 bubbles per 2 seconds.

3)How long have you been using this type of setup?
One month.

4)Have you experienced any problems with this setup?
The needle valve resolved the problem of adjusting the flow rate with
minimal fuss.

5)If you could change something(s) about your current setup, what would
it
be?
The Eheim diffuser!  Even with the needle valve, adjustments are not
immediate due to pressure in the line (I assume).  In order to reduce
flow rate I need to make a small adjustment with the needle valve and
then check it later when the line pressure reduces. Also, while the
diffuser does create very tiny bubbles many of them reach the surface of
the water.  I have moved the diffuser under the intake of the Magnum 350
cannister intake and it makes a big difference.  However, as someone
else pointed out it is not a good solution for maintenance of the
diffuser and it is not visible.  Maybe someone can help me with this one
- - how does CO2 into the cannister affect the biological aspect of the
filter?  At any rate, I am planning on ordering a CO2 reactor - possibly
external.  I will post some reactor questions later.

6)What cV flow rates do you use?
I don't know.  AL says the valve has 4 turns of revolution,  maximum
flow equal to a CV of 0.09, and maximum pressure of 125 psi.  What is CV
flow?

BTW    I started running this system closer to 15psi, but blew the hoses
off the valve or regulator several times.  I used some zip ties (the
plastic things that hold bunches of wire together) because I was to lazy
to use silicon.  They held the hose on the valve, regulator, and check
valve just fine.  I reduced the pressure several days later.

Jay Reeves


Reactors vs diffusors

by Erik Olson <erik/thekrib.com>
Date: Sun, 28 Jan 2001

On Sun, 28 Jan 2001, Robert H wrote:

> I would like to hear from people what the differences are between reactors
> and diffusors...(those that release a fine mist of bubbles).
> 
> Do reactors saturate the water more with CO2 than diffusors? 

yes, definitely.

> To what extent?

100% dissolution in water, as opposed to the bubbles, many of which escape
out the top of the tank before even dissolving.

> Is CO2 that is mixed with water before being released into the aquarium more
> stable? Anotherwords does CO2 from a diffusor burn off somehow quicker? What
> role does circulation in the tank play?

I don't think that there is any difference between the two methods ONCE
the CO2 is actually dissolved in the water.  The problem is simply that
diffusors let gas escape out the tank before it is dissolved to begin
with, while reactors trap the gas in a sealed chamber until it dissolves
in the water.

> What are the advantages or disadvantages of either method?

Bottle + Regulator + needle valve + reactor
- -------------------------------------------
PRO can be 100% efficient, fast dissolving, little cleaning required
CON bulky and/or external, requires water flow, bubble counter
May be cheaper, or more expensive... Pro or Con?

Bottle + Reg + Glass diffuser 
- -----------------------------
PRO simple, not intrusive in tank, self-contained
CON dumping problem, algae build-up, difficult to adjust, inefficient

Bottle + Reg + powerhead/canister diffusion
- -------------------------------------------
PRO easy, works with existing hardware, no dump problem
CON even less efficient than diffusor

inverted bell
- -------------
PRO simple, can be efficient, fairly safe (vents excess out bottom)
CON bulky and ugly, and inefficient RATE of dissolving

  - Erik

- -- 
Erik Olson
erik at thekrib dot com


Aquatic Plants Digest V4 #809

by Chris Schmelzer <chris/coffeecafes.com>
Date: Tue, 30 Jan 2001

> Bottle + Regulator + needle valve + reactor
> - -------------------------------------------
> PRO can be 100% efficient, fast dissolving, little cleaning required
> CON bulky and/or external, requires water flow, bubble counter
> May be cheaper, or more expensive... Pro or Con?
> 
> Bottle + Reg + Glass diffuser
> - -----------------------------
> PRO simple, not intrusive in tank, self-contained
> CON dumping problem, algae build-up, difficult to adjust, inefficient
> 
> Bottle + Reg + powerhead/canister diffusion
> - -------------------------------------------
> PRO easy, works with existing hardware, no dump problem
> CON even less efficient than diffusor
> 
> inverted bell
> - -------------
> PRO simple, can be efficient, fairly safe (vents excess out bottom)
> CON bulky and ugly, and inefficient RATE of dissolving


I don't understand how the canister diffusion technique is LESS efficient
than a diffusor... If you really think about it, it is actually MORE
efficient and probably the same as a reactor (at least in my setup).. I
bubble my CO2 (pressurized, regulator, needle valve, bubble counter, then
into the intake of my Eheim) and I RARELY get a belch from my spray bar
(submerged).

What does this mean?  Almost ALL the CO2 put into the Eheim ends up in the
water, which equates to close to 100% efficiency, MUCH better than a
diffusor in which a significant percentage of bubbles make it to the surface
undissolved...


Eheim diffusor clogging

by Dave Gomberg <gomberg/wcf.com>
Date: Wed, 20 Jun 2001

For a very long time I had assumed that all Eheim diffusor "clogging" was 
due to algae and devised a way to clean the sintered glass disk which 
method is described on http://www.wcf.com/co2iron/faq.html

More recently a user told me he had big bubbles (which he associated with 
"clogging") but no green stain on the disk.   I thought about this way way 
too long, and finally realized (1) what is going on and (2) why I never see it.

(1)  What is going on?   If you have a lot of calcium cations in your water 
(usually from contact between the water and a relatively soluble calcium 
salt) (this is called hard water) and you now bubble CO2 thru it, the CO2 
dissolves in the water, disassociates, and the carbonate anions react with 
the calcium producing calcium carbonate, which is white.   This is a pretty 
fast and complete reaction.   The result is the deposition of a white crust 
on the disk (almost invisible).  The fix is to dissolve the crust off with 
a strong acid, this procedure is now described on the web page cited above.

(2) Why I never see it?   I have very soft water.

Next case.....




- --
Dave Gomberg, San Francisco       gomberg at wcf dot com
NEW Planted Aquaria Magazine:        http://www.wcf.com/pam
- -----------------------------------------------------------------


re: CO2 FAQ

by Erik Olson <erik/thekrib.com>
Date: Wed, 20 Sep 2000

On Tue, 19 Sep 2000, DaTrueDave wrote:

> Ok, I've gone back and reread Dave Gomberg's co² FAQ.  It does contain
> a lot of good information!  However, he mentions several times that a
> "low pressure" system isn't as stable as a "high pressure" system.
> I've been leaning towards wanting a low pressure system, but now I'm
> hesitant... 

Of course.  This is the problem with anyone with a vested interest
providing "free" information on the side (sorry Dave).  Of course Dave
will say the ceramic disk approach is better.  That's what he believes in
and sells.

I'll say right upfront that my experience with the ceramic diffuser is
different.  Being a big proponent of unbiased comparisons, I bought an
eheim diffuser a year and a half back and tried it out. After a day or
two, it "popped" and killed a tank of fish. I don't use them now.  After
hearing that it can happen at the end of the tank as well, I don't think
it's worth it for my tanks (most of which are breeding tanks with fish
worth more than the CO2 system, let alone the delta between an eheim and a
good needle valve).  On the other hand, I've never lost a fish in my tanks
fed with even the crappy ARO-1 valves.  So that's MY bias.

> Here's the section of the FAQ that confuses me:
> <<<What's the difference between high pressure and low pressure
> systems?
> A low pressure system runs about 1 psi, a high pressure system about
> 15 psi. A low pressure system is hard to regulate. The regulator will
> regulate well from about 10-25 psi. A low pressure system needs a way
> to drop the 10 psi to 1 psi. Ususally a needle valve is used, but this
> is not very reliable, since a needle valve is not designed to regulate
> pressure, but flow. 

As Wright is so fond of writing, "HOGWASH!"  All systems ultimately are
delivering CO2 by means of flow.  The flow is very low, but it is still
flow.  The needle valve system (I hesistate to call it low pressure.  See
below) is designed to put out 1~5 bubbles per second.  The ceramic disk
method is designed to put out a fixed number of microbubbles per second
(I'd presume about the same volume as the needle?).

> If you set the regulator very low, the pressure
> will wander up and down. If you set the needle valve almost closed (as
> you must to make a big pressure drop) the flow rate will vary a lot.

Most everyone using a needle valve sets the pressure of the regulator
between 5 and 20 PSI, which is quite reasonable, and sets the needle valve
to a very low flow.  If it's a cheap needle valve (i.e. the infamous
ARO-1), fluctuations occur, but it's not too bad if one keeps it in the
same place and roughly the same temperature.  If it's a $40 needle valve
like the Nupro, the fluctuation is very low and stability very good.

Now this whole thing of calling the diffusers "high pressure" and the
needle valve system "low pressure" is a bit misleading.  Both systems have
a "first stage" pressure regulator (the standard CO2 regulator) that is
set roughly the same (though the ceramic disk requires a more precise
setting... too low, no bubbles will get through the disk; too high, the
thing will pop).  Both systems have a "second stage" (the needle vs. the
ceramic diffuser) that regulates the flow down to about the same rate.  
The only difference is that the needle valve is usually coupled near the
regulator, while the diffuser is coupled far away from it.  OK, I don't
want to start another American Flagfish Naming Debate, so I won't bring it
up again.

Anyway, my take on the pros and cons between them.  

Needle valve/"Low Pressure"
PRO	allows actual control of flow by adjusting the needle
	does not suffer from "end of tank" dump
	all high pressure parts are coupled near the tank
	downstream reactor can be more efficient than ceramic diffuser

CON	more expensive if low fluctuation is desired
	requires reactor, powerhead, or diffusion bell downstream		
	requires fiddling with needle to get right flow right


Ceramic Diffuser/"High Pressure"
PRO	diffusion built-in.  compact, non-intrusive in tank, and cheap!
	cheaper than good needle valve
	no fiddling, just set regulator pressure
	very stable output through most of CO2 tank life

CON	no ability to set CO2 diffusion rate.  range is limited
	suffers from end-of-tank problem
	potential hazard of dumping all CO2 into tank if diffuser "pops"

  - Erik

- -- 
Erik Olson
erik at thekrib dot com


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This page was last updated 17 February 2002