Co2 Diffusers

[Mandy]

In my endless research on the net these past few days I've read all
sorts of DIY Co2 methods - from the very expensive and / or complicated
(needles, gages, tanks, etc.) to the very simple
http://www.fishforums.com/phpBB/viewtopic.php?t=17651

and equally complicated information on diffusers - until I came across
this posting
http://www.aquaticplantcentral.com/forum/viewtopic.php?t=329&postdays=0&postorder=asc&&start=15
suggesting the use of either a filter from a cigarette - you change it
every time you hook up a new bottle - or a bamboo (balsa?) chopstick
stuck into the airtube.

Anyone here have thoughts on either of those? I'm looking for SIMPLE.
:D

Tank - 37 gallon eclipse - no powerheads, just a bio wheel with an
intake ummm thing.

I've also read some really scary stories of DIY Co2 systems going awry
http://www.thekrib.com/Plants/CO2/yeast-disaster.html

My landlord will KILL me if I explode yeast all over the walls. I'm
already not supposed to have a tank larger than ten gallons but he's
seen it and not said anything... He was pretty nice about my "illegal"
painting of all the walls, too. I'd like not to try his patience with a
yeast explosion... lol

[Michi Henning]

"Mandy" > wrote in message
ups.com...
>
> and equally complicated information on diffusers - until I came across
> this posting
>
http://www.aquaticplantcentral.com/forum/viewtopic.php?t=329&postdays=0&postorder=asc&&start=15
> suggesting the use of either a filter from a cigarette - you change it
> every time you hook up a new bottle - or a bamboo (balsa?) chopstick
> stuck into the airtube.
>
> Anyone here have thoughts on either of those? I'm looking for SIMPLE.
> :D

One of the simplest ways to make a diffusor is to attach a bell-shaped
container upside down with a suction cup to the glass and bubble the
CO2 into the bell from underneath, so it is trapped there. That way,
the CO2 can diffuse into the water. (A flatter shape bell is better than
a narrow tall one -- the idea is to maximise the surface area where the
CO2 is in contact with the water.) One disadvantage of the bell is
that you periodically have to empty it out (every few days or so) because,
over time, not only does CO2 dissolve from the bell into the water, but
nitrogen and oxygen diffuse from the water into the bell. After a while,
you end up with a gas mix that isn't pure CO2, which slows down
the diffusion.

Another option is to use a wooden air stone but, personally, I prefer
diffusors that trap the CO2 to increase contact time with the water
because, even with very fine CO2 bubbles, you tend to lose a lot
from bubbles that make it to the surface.

The best reactor I know of is the Aqua Medic Reactor 1000.
http://www.aqua-medic.de/cgi-bin/php/display_product.php3?p_id=114&lang=en&cat_id=12

Dupla make a diffusor that's essentially identical. These things really
work extremely well. You can build a homemade version of this for
under $20.

Aqua Medic also make a reactor that uses a semipermeable membrane
to diffuse the CO2, but I have no personal experience with it.
http://www.aqua-medic.de/cgi-bin/php/display_product.php3?p_id=7&cat_id=12&lang=en

I'd be interested in hearing from anyone who has tried that reactor
and can report on how well it works.

Cheers,

Michi.

--
Michi Henning Ph: +61 4 1118-2700
ZeroC, Inc. http://www.zeroc.com

[Ozdude]

"Mandy" > wrote in message
ups.com...
> In my endless research on the net these past few days I've read all
> sorts of DIY Co2 methods - from the very expensive and / or complicated
> (needles, gages, tanks, etc.) to the very simple
> http://www.fishforums.com/phpBB/viewtopic.php?t=17651
>
> and equally complicated information on diffusers - until I came across
> this posting
> http://www.aquaticplantcentral.com/forum/viewtopic.php?t=329&postdays=0&postorder=asc&&start=15
> suggesting the use of either a filter from a cigarette - you change it
> every time you hook up a new bottle - or a bamboo (balsa?) chopstick
> stuck into the airtube.
>
> Anyone here have thoughts on either of those? I'm looking for SIMPLE.
> :D

I think I am going to try and hybridize the DIY CO2 designs I have seen
because I have concerns about an explosion, gas absorbtion and rotting the
diffuser and impellor of my internal filter by "dribbling" CO2 into it's
inlet.

I am prepared to use silicone sealant over model jet plane seals, and
silicone pipes over CO2 resistant ones, just because I can't afford the more
expensive stuff right now. For all I know my plants may not need any CO2
injection. I won't know until the tank is up and running for a couple of
months.

The web sites you quote above have a thread and link that leads to a skimmer
wood air diffuser which is made from Basswood;

I am going to modify this design to make a submersible one which will fit
inside a small DIY reactor through which the spray bar (submerged) will be
outputting through.

My theory is that the bubbles from the basswood will be small, and smaller
again after passing through some bioballs before the water current hits
them. I have no way of measuring CO2 levels, but that's my theory anyway.

As for the reactor itself, I am going to buffer it by using an additional
1.25L bottle (the buffer) next to the generator bottle with nothing more
than CO2 in and out (to the diffuser). The line out from the buffer to the
diffuser will have a blow valve somewhere on it because I really don't want
to wake up one day to a smelly splattered room if things don't go right.

I also plan to buy what they call a "shopping bag bin" here in Australia
which the bottles will be sealed in. They are PVC and can be sealed around
the lid - just as extra protection from a bottle explosion and it'll look
neater than two juice bottles with pipes all over ;)

It's worth noting also that the thread about the chop stick lead to a
comment where the guy said it actually worked by producing little tiny
bubbles. I wonder if you stuck enough chopsticks together if you could make
a DIY wooden diffuser with them, after reading that. I think the wood they
use would rot though so there may be no advantage to it over buying a LFS
wood stone.

I'll keep you informed on my soon the be established web page for
cheap/effective DIY Aquarium things ;)


Oz

[Mandy]

Awesome, Oz! photos and drawings are really helpful, too. I'll let
you know how mine goes if I can get past this hangover to go buy
supplies.

Michi - thanks for the info. I'll see if I can build a bell over my
chopstick! lol

Happy New Year! I was in Sydney for the millenium celebrations - you
guys definitely know how to throw a party!

[Michi Henning]

"Mandy" > wrote in message
oups.com...
>
> Happy New Year! I was in Sydney for the millenium celebrations - you
> guys definitely know how to throw a party!

That's probably Australia's main claim to fame: all
you need to have a really good time is a BBQ and
carton of beer ;-)

Cheers,

Michi.

--
Michi Henning Ph: +61 4 1118-2700
ZeroC, Inc. http://www.zeroc.com

[Ozdude]

"Mandy" > wrote in message
oups.com...
> Awesome, Oz! photos and drawings are really helpful, too. I'll let
> you know how mine goes if I can get past this hangover to go buy
> supplies.
>
> Michi - thanks for the info. I'll see if I can build a bell over my
> chopstick! lol
>
> Happy New Year! I was in Sydney for the millenium celebrations - you
> guys definitely know how to throw a party!

Well the fireworks were just incredible as usual. I keep wondering how much
longer it can keep getting better? This year I saw pastel colours I've never
seen before in fireworks. On TV they were calling Sydney "The NYE capital of
the World!" - bah! We just have good fireworks and good people.

This year we have a giagantic "disco ball" hanging off the Harbour Bridge
that has Vari-Lites on it - the biggest mirror ball I've ever seen - the
whole city is in party mode right now - tempered with respect for the
Tsunami victims in S.E. Asia.

;)

Oz

[Ozdude]

"Michi Henning" > wrote in message
...
> "Mandy" > wrote in message
> oups.com...
>>
>> Happy New Year! I was in Sydney for the millenium celebrations - you
>> guys definitely know how to throw a party!
>
> That's probably Australia's main claim to fame: all
> you need to have a really good time is a BBQ and
> carton of beer ;-)

Only an Aussie could say that :). Are you from Oz? Canberra or something????

Oz

[Michi Henning]

"Ozdude" > wrote in message
...
> >
> > That's probably Australia's main claim to fame: all
> > you need to have a really good time is a BBQ and
> > carton of beer ;-)
>
> Only an Aussie could say that :). Are you from Oz? Canberra or something????

No, Brisbane. But the barbie and the beer work up here
just as well as they do in Canberra ;-)

Cheers,

Michi.

--
Michi Henning Ph: +61 4 1118-2700
ZeroC, Inc. http://www.zeroc.com

[Mandy]

Okay, built my Co2 reactor, bought a cool German diffuser / bubble
counter and I'm getting one bubble every five seconds. Is that enough?
The bubble goes thru a housing and then passes thru a porcelain piece
which is supposed to make for fine bubbles - but I seem to be getting
one fat bubble every five seconds... is that right?
What is a bubble counter, exactly?

[Captain Feedback]

I use a Hagen "Natural Plant System" diffuser in my 29gal heavily
planted tank. You can buy this diffuser separately from the whole,
bogus kit.

I have it connected up to a 2qt juice bottle of yeast-sugar-water mix.
I get plenty of CO2 from this setup. Not only do I use a HOB AquaClear
filter (surface agitation! horrors!), but I have to actually use an
airpump to blow off excess CO2. I easily get 25ppm of CO2.

[Captain Feedback]

A bubble counter is any device that lets you count how many bubbles of
CO2 is going through your diffuser/whatever. But it's only meaningful
if you have some baseline so that you know that "X" number of bubbles a
second gives you enough CO2.

A better thing to do would be to get a good KH and pH kit, measure your
KH and pH, then go to this page:
http://www.csd.net/~cgadd/aqua/art_plant_co2chart.htm