DYI CO2

[Pandora114]

Not like I plan on using it since I love Flourish Excell and the Seachem plant fertilizer line (Heck I'm not gonna put anything in my substrate, I can leave it as is..it's natural riverbed gravel) BUT, in a pinch, I made this lovely little co2 dealio.

1: 2litre Pop bottle with cap
2: 1 Air Hose
3: 1 Air Stone, finer the bubbles the better
4: Some blu-tac
5: Champange Yeast (You can get this at your local U Brew store)
6: 2 cups of Sugar
7: 4 cups of WARM water
Step 1, clean the pop bottle and let dry
Step 2: poke a hole in the bottle top and snake the air hose through put cap on loosely, the hose should come JUST above the half way mark in the bottle. Put air stone on the part of the hose that is going into the tank
Step 3: Seal any open areas around air hose with blu-tac
Step 4: pour in yeast, sugar and warm water. (use a funnel for less mess of course)
Step 5: Twist cap on tightly. Use plyers if you gotta, but since it's meant to keep things airtight to prevent soda from going flat, you can get it pretty darned tight.

No need to shake or anything, just put the stone in your tank, and let the bubbles do the work.

I choose champane yeast because it's perfect for making tons of bubbles, for a very very long time. One bottle set up like this, lasts me a whole month.

[julianchan]

Good setup. I would like to add one more step in this process. After your 2 liter pop bottle, you might want to add another bottle to the picture. A smaller pop bottle will work. Basically one tube into the bottle, and another tube out. Sealed tight just like the first bottle. What this does is to make sure only your CO2 is getting into your tank, and removes any other impurities that potentially can build up as solids, or liquids.

[Agnate]

I would suggest a slightly modified setup (which includes Julianchan's mod).

Basically, instead of using just 1 bottle, you use 2. You "plumb" them together using a T-valve, and the single tube runs into the bottle that Julianchan described. From that bottle, you run the tubing into the tank.

The idea of this setup is a consistent and stable amount of CO2. So I pour 2 cups of sugar into the bottle, 1 tsp of bread yeast (I've never used champagne yeast, so you'd have to adjust accordingly), and then fill the bottle with lukewarm water until it hits the line where the midsection of the bottle begins to turn into the neck (about 3/4 the way up). You just do this for the first bottle, and just fill the second bottle with water (for now). Next week, you do up the second bottle like you did the first. On the third week, you replace the first bottle with a new batch of yeast-sugar-water. Keep alternating every 1-2 weeks (and write out a schedule, heh), and you'll have yourself a nice, stable, and consistent CO2 machine.

[taureandragon76]

Also a good idea to install a check valve in the system so nothing drains out on you. As far as champagne yeast it's the same measurement, it just reacts quicker and lasts longer.

[julianchan]

I had 2 check valves in my system, one between the first bottle and second (so I dont lose pressure when changing bottles) and one between the second bottle and the tank to avoid syphoning.

[taureandragon76]

When I had my 50g setup I used a 4 L bottle and I found I had better luck and less algae problems then when I switched over to pressurized.

[Troender]

This is the setup I use (scroll down to post # 38).

And the mix I use to get CO2 is:
4 deciliters of hot water
4 deciliters of sugar
Shake until the sugar is dissolved
4 deciliters of cold water
1 teaspoon of baking powder
Shake
1-2 teaspoons of dry yeast
Do not shake - the yeast is supposed to float on the top.

[Agnate]

I don't think I've *ever* measured out something is decilitres, haha!

[Dadof4]

I don't think I've *ever* measured out something is decilitres, haha!

I held my tongue on that one.....I'm glad you said it!

[Jase]

I've never even heard of a deciliter...
What's the baking powder for?

[julianchan]

I think it helps activate the yeast better....makes it more...whats the word..productive?

[J-P]

I think it helps activate the yeast better....makes it more...whats the word..productive?

baking powder only serves as a stabilizer ... it is totally unnessessary in CO2 production... beer / wine that is different
sugar water ... will activate the yeast ... yeast feeds off SUGAR .... dextrose is the best and can be found at your local bulk food store .. if not then icing sugar, maple / corn syrup (pure) is also good.

Unlike bacteria, yeast doesn't propage once the disolved sugars are absorbed. You might be able to get your yeast to go through 3x5 day batches at best. I refreash mine ever week.