DIY Yeast CO2

Do it yourself - Co2 generator for planted aquariums

http://www.plantedtank.net/articles/DIY-Yeast-CO2/7/

Since DIY C02 is a pretty popular method of injecting C02 into small tanks 30 gallons or less I've made an article to help anyone in the process of making a C02 unit. So lets just get right into it.

First were going to need a few things to make the unit. These include:
- A drill
- A few feet or airline tubing
- A pair of scissors
- A sealant
- A checkvalve (optional)

Now first you have to take the drill and find a bit that is just a little smaller then the diameter of the tubing (the kind of tubing you choose does'nt matter much, I used silicon because it has a little more resistance to C02 and will last a little longer than the normal clear tubing, but its fine if you choose the regualr tubing).

Then cut the tubing down to the size of which it will be ran to your tank, also make sure to leave some loose tubing just incase you need to resituate the bottle or anything else dealing with the length of the tube. Then drill a hole in the center of the cap and fit the tubing in as snug as you can get it. Only put the tubing in 2-3 centimeters. After this is done you are ready to seal the cap.

So now bring out the sealant and get some in the cap against the tubing to make a seal. Let it sit for 30 minutes to an hour for it to dry somewhat. Then repeat the same thing for the top and let it sit. After your done sealing the tube don't mess with it much because it may move the tube and make it a less secure seal.

Now you may want to wait a full day just to make sure your sealant is fully sealed. Don't be impatient you'll probably end up resealing it if you do put it to use too soon. By now you have finished making the C02 unit and you are ready to make the C02 mixture. This is what the end product should look like:

But before we jump right into making the mixture lets talk about methods of Diffusion. \

There are tons of methods to diffuse the C02 into your tank. To list just a few there are:
- C02 Reactors
- Diffusion Unit
- Injection into a Power Filter
- Airstones

Of course there are more but I dont want to get that detailed into the diffusion. If you are running a power filter just stick the tubing into the intake and the impellar will dissolve the C02 very well. Another easy method is an airstone, but let me tell you from my experience that it is a poor method and most of the C02 doesn't dissolve into the water. So I'd stick with the filter intake method it works great.

--How to make the Mixture--

Okay now to make the mixture we need a few things:
- The 2L Bottle
- Sugar
- Yeast
- Measuring Spoon
- A funnel

I use the mixture of 2 cups sugar and 1/2 tsp of yeast. There are other mixtures and they have other affects. More yeast means the mixture will produce a lot of C02 but not last as long, as the yeast eats the sugar and a biproduct is the C02. So with this 1/2 a tsp it produces a constant C02 for a longer period of time, I would say for 3 weeks and the 1 tsp mixture lasts 2 weeks or less. Whatever you choose is fine, but I recommend the 2 cups and 1/2 tsp yeast.

Now take the bottle set the funnel in the top and get ready to pour in some sugar and yeast (you could use a piece of paper for a funnel if you dont have one, but i fortunately found one around the house). Now add the 2 cups of sugar, and the 1/2 tsp of yeast. Then its time to add the water. To get a good start of C02 production we want to use luke warm water, dont use hot water because this will kill the yeast. Fill the bottle with water up to the brim were it starts to curve into the top. Im not sure how to explain this that well, but just leave a 3" gap between the water level and the top.

Now you have the 2 cups of sugar, 1/2 tsp of yeast, and the water in the bottle. Find a cap and shake up the mixture well and then let hook it up to your sealed cap which should be hooked up the tank in your diffusion method that you chose. Dont leave the undrilled cap on the mixture and forget it, you will come back to a huge mess, remember this produces C02 and if its not left a point to exit it will turn into a bomb. Now that its hooked up it should take and hour or two to start producing. It may take a day depending on the temperature of water you used and if the yeast is active. Also remember to shake it up everyfew days to keep the unit producing C02.