# My DIY gelatine CO2 element



## Error (Apr 16, 2004)

Hi guys,

I just wanted to get some feedback on my current setup. I'm planning on going pressurized as soon as I can accumulate the extra cash, but for now I'm working with a DIY setup. Here are the specifications:

I use gelatine in my yeast reactors. I originally got the recipe from anonaperson (who can be credited with testing and perfecting the method). For those of you who haven't heard of this method of DIY CO2, this is the formula:

I start with 1 cup cold water in an 8" x 8" brownie/cake pan with 4 packets Knox brand gelatine powder ($1-2 at most grocers) evenly mixed in. Then I take 2 cups sugar and 2 cups water and combine the two in a medium saucepan and heat on the stove until just below boiling. I stir this to make sure the sugar dissolves entirely (the water goes clear when it has) and then I add this hot mixture to the cake pan with the gelatine and cold water. This I stir until the gelatine in the pan has dissolved (takes a few minutes). Then I refrigerate the pan overnight.

The next day I remove about a third of the now-firm gelatine and cut it into cubes/similar shapes that are small enough to fit through the top of a 2 liter bottle, and I replace the remaining gelatine in the fridge for future use. I put the cubes into the bottle and set this aside. I then activate the yeast by stirring half a teaspoon of sugar into 1 cup of tepid (slightly above room temperature) water and dropping about 1/4 teaspon of bread yeast on the surface. These I let go for maybe 2 or 3 hours; it's important that the gelatine gets to room temperature and a layer of foam develops on the surface of the yeast cup.

Next I add the yeast through a funnel and fill the bottle up with tepid tap water to about the place where the upper curvature of the bottle begins. I then screw on the cap, which is drilled to accomodate an airline tube that is inserted about half an inch and sealed in place with silicone. The end of this I affix to a metal gang valve along with 3 other bottles that have been prepared the same way, and I run the hose up to my bubble ladder (this I need to replace in favor of a more efficient diffuser).

The reason I use 4 bottles total is because my basement is a bit cooler (~65-70 degrees year-round). This apparently slows the metabolism of the yeast and I don't get as large a flow as people whose setups are in nice, warm rooms. I make up for this disparity with multiple bottles.

Anyone have any thoughts or suggestions?


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## gpodio (Feb 4, 2004)

Hi there, I used to use the "jello" method too, but I never thought of making cubes :roll: I used to actually pour the jello mix into the soda bottle, let it set in the fridge and then add yeast and water on top. It worked great for smaller tanks as it regulated the output and slowed it down, I also found that the reduced amount of water made the mixture become toxic earlier than normal, but that was easy to fix as I'd tip it out leaving the remaining jello stuck to the bottom of the soda bottle and just add fresh water and yeast again. At some stage however I got lazy and started to do the regular DIY method, then I got married and had to go pressurized :wink: 

Regards
Giancarlo Podio


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## anonapersona (Mar 11, 2004)

*Warm sump?*

If you have room for a small 10 gallon tank under the stand, you could set all the bottles in that and fill with water (not enough to make the bottles float!) and add an aquarium heater to keep the bottles at something warmer than room temp.

Somewhere along the way I saw a photo of someone using a bucket to do this, but for that many bottles you'd want a 10 gallon tank.


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## Error (Apr 16, 2004)

Hmm...that's an idea. Unfortunately funds are tight at the moment so it'll have to wait a few weeks, but thanks for the idea


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