Re: DIY CO2 pressure

>I use a 2 liter soda bottle for my CO2 reactor and mix 2 cups of sugar
>and 1/4 teaspoon of yeast and water filled up to 2" below the cap cover,
>so far the CO2 generated is only about 2 ~3 bubbles per minute
>.... Is this sufficient ?

Yes if you have a good reactor. What you describe is a generator. A reactor
holds the CO2 in the tank long enough for it to dissolve.

>1. How can I increase the rate of CO2 output and what is the normal
>   rate of CO2 generated from this type of DIY system ?

There is no "normal" since conditions vary so much and the systems are not
precise; they're do-it-yourself. Try using 1/2 teaspoon of yeast and 4 cups
of sugar. That's what I use. Also add 1/2 teaspoon of baking soda to keep
the mixture from becoming acid too quickly.

>2. I also experience very low CO2 release pressure into the tank when I place
>   the soda bottle higher than the water level of the tank. Where should the
>   soda bottle be placed to get a reasonable gas release pressure into the

I'm puzzled. My soda bottles are up to 2 feet *below* my tank. You should
not have a problem with pressure unless there is a leak along the way.

>3. What are the methods use to connecting the CO2 line into the tank ?
>   .... to diffuser, or power head ?

The gas has to be sent to a reactor in the tank. A powerhead will work
fine. If your powerhead has a venturi air intake, connect the airline from
your generator to the venturi hole. If you use a canister, just bubble the
CO2 into the water intake of the canister; the CO2 will dissolve inside the

There are different reactors in the archives of The Krib, Web site. A very
easy reactor for use with a powerhead without a venturi air intake is a
1/2" flexible hose, about 8" long, attached to the water outlet of the
powerhead. Connect the airline from your generator to a drip irrigation
connector. Stick the connector into a hole in the 1/2" hose. The longer the
distance between the connector and the open end of the hose, the more CO2
will dissolve.

Greg. Tong
San Francisco, CA, USA
gtong at sirius_com

"Every infinity is composed of only two halves."