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DIY CO2, bubbles not forming in bottle

2206 Views 18 Replies 11 Participants Last post by  kaaayd
I have a dilemma. A long time ago I could make DIY CO2, but the last three tries I have failed. I tried again just a few minutes ago, and I know it's too early to tell if it worked, but I doubt it's going to bubble. Here's what I did:

1) Applied another layer of hot glue to the soda bottle cap and the air tube just to make sure there are no leaks.
2) Put 2 cups of sugar and 1/4 tsp of yeast in the bottle.
3) Filled a small amount of the bottle with cold water, and then filled the rest with hot water, to make it warm.
4) Added Prime.
5) Shook the bottle.
6) Hooked up to tank.

Right now I'm seeing the yeast particles just floating in the mixture. I'm pretty sure this means it's dead. And this was a brand new pack of yeast too! If I'm doing anything wrong, please tell me. Thanks.
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It takes time. I had a Red Sea version it took 24-36 hrs to start making co2
I have a dilemma. A long time ago I could make DIY CO2, but the last three tries I have failed. I tried again just a few minutes ago, and I know it's too early to tell if it worked, but I doubt it's going to bubble. Here's what I did:

1) Applied another layer of hot glue to the soda bottle cap and the air tube just to make sure there are no leaks.
2) Put 2 cups of sugar and 1/4 tsp of yeast in the bottle.
3) Filled a small amount of the bottle with cold water, and then filled the rest with hot water, to make it warm.
4) Added Prime.
5) Shook the bottle.
6) Hooked up to tank.

Right now I'm seeing the yeast particles just floating in the mixture. I'm pretty sure this means it's dead. And this was a brand new pack of yeast too! If I'm doing anything wrong, please tell me. Thanks.
Hi Overgrowth,

I suspect that the hot water is killing your yeast. I had the same problem for several batches of DIY (when I was doing DIY). I found the trick was to fill the bottle with lukewarm (body temp) water then add yeast and shake. Also, I never connected my tubing until the bottle dropped to room temperature to avoid a suction occurring as the bottle cooled and sucking the water out of my tank.
Hi Overgrowth,

I suspect that the hot water is killing your yeast. I had the same problem for several batches of DIY (when I was doing DIY). I found the trick was to fill the bottle with lukewarm (body temp) water then add yeast and shake. Also, I never connected my tubing until the bottle dropped to room temperature to avoid a suction occurring as the bottle cooled and sucking the water out of my tank.
I don't think that's the problem. Firstly, I put a little cool water in the tank before I put in the hot water to balance the temperature. After the bottle's filled up, the top feels warm, but the bottom still feels cool. Secondly, the water at its hottest doesn't exceed 90-93F.
Idk if you're doing anything wrong, But here is what works for me.

-Take 2 cups of sugar & pour hot or warmish water over it (in a bowl or something) then dissolve it whisking your finger in the bowl.
-Once that is done put cold water over it just until it is barely warm & then pour it into the bottle.
-After that pour new warmish water into the bottle until it is almost to the brim
-Take a ziplock bag & put slightly warm water about half way up with the yeast
-lock the bag & shake it around until it is mostly dissolved
-Now pour it into the bottle & you should get c02 in 12-24 hours

& when it comes time to make new c02 I pour maybe 1/3 of the old contents out & add sugar water to the existing mixture (no need to add yeast)
I don't think that's the problem. Firstly, I put a little cool water in the tank before I put in the hot water to balance the temperature. Secondly, the water at its hottest doesn't exceed 90-93F.

I do the water at maybe 60ish pretty cold but it always works
Also, I use Fleischmann's (sp.) yeast. If there's a yeast that has a higher success rate, could someone please share? Thanks.
I heard a lot of people like wine yeast. But I'm using the exact same yeast you're using. diy c02 off the same batch for 1 1/2 months now
Yeah, the Fleischmann's yeast has worked for me several times in the past, but I just can't get the yeast to bubble anymore.
Are you using a new package? I would try again but use colder water, the initial start up would be slower but you wouldn't run the risk of burning the yeast & for the tubing to the cap I never use a glue gun.. I just can't get a good seal with it. I used to use sealant but I hated waiting long for it to cure so now I just use super glue...take the tubing & put it in about an inch then put superglue on the top around the tubing & pull down. Works everytime
Are you using a new package? I would try again but use colder water, the initial start up would be slower but you wouldn't run the risk of burning the yeast & for the tubing to the cap I never use a glue gun.. I just can't get a good seal with it. I used to use sealant but I hated waiting long for it to cure so now I just use super glue...take the tubing & put it in about an inch then put superglue on the top around the tubing & pull down. Works everytime
The previous two tries I used colder water than the current attempt, but there were no bubbles.
You need very warm water to activate the yeast. Cool/cold water won't do it. There are probably as many "recipes" out there as people who use them, but the "proofing" of the yeast is pretty close in all of them. Here's how I used to do it:

Put your sugar in your pop bottle. Fill the pop bottle with the warmest temp the yeast will tolerate (110 F). Shake to dissolve the sugar completely. Pour a small amount of that mixture into a cup (preferably pre-warmed but if it's thin walled plastic like a measuring cup I would skip this step). Sprinkle your yeast into this liquid and give it a gentle stir. WAIT UNTIL THE YEAST IS FOAMING. 10-15 minutes usually. Then add this mixture back into your main bottle. Add your pinch of baking soda now if you want to. Seal and go.

The key is that you're using the SAME mixture to proof the yeast as what it will be living in ever after.
I just throw everything in the bottle and shake. Takes a few hours to start, but it works for me every time so far.
I pour in a 1/2 tsp of yeast into my clean bottle.Add a cup of luke warm water to
the bottle and swirl the mixture around in the bottle and wait 10-15 minutes.
I then add my 2 cups of sugar and then fill the the 2 litre bottle 2/3 filled with luke warm water again .I then give it a pretty good shake to dissolve the sugar.
It has started working for me in as little as in hour and as long as 24 hours.Leaks are usually the main culprit for lack of co2 output.
You'll get it. I like this link:
http://www.aquatic-eden.com/2006/09/diy-co2-recipe-duration-vs-intensity.html
Yep I use flieschmanns as well currently and have done the long process as well as the throw it all in from boiling to Luke warm water. The only time it didn't work is when I had a leaky cap.
Put your sugar in your pop bottle. Fill the pop bottle with the warmest temp the yeast will tolerate (110 F). Shake to dissolve the sugar completely. Pour a small amount of that mixture into a cup (preferably pre-warmed but if it's thin walled plastic like a measuring cup I would skip this step). Sprinkle your yeast into this liquid and give it a gentle stir. WAIT UNTIL THE YEAST IS FOAMING. 10-15 minutes usually. Then add this mixture back into your main bottle. Add your pinch of baking soda now if you want to. Seal and go.
This. Treat the yeast like you would if you're baking bread. It really helps to proof it first because it starts bubbling faster and you can double check that your yeast is alive.
1) Bottle caps are made of polyethylene, which (without some exotic techniques) cannot be glued. If it's not leaking now, it WILL leak later! The simplest way to get a reliable and long-lasting tubing connection is to drill a hole slightly smaller than the tubing, cut the tubing at an angle, and pull it through. However, your existing cap can be salvaged. Remove all glue, push the tubing through the hole, and shove a tubing coupler (or similar, like a plastic part from an airstone) from the inside of the cap into the tubing, expanding it into a snug fit.

2) The only time I've ever tried 1/4 tsp. of yeast, it failed to produce CO2. Sugar water does not provide all necessary nutrients for life. Yeast live in it only by recycling a limited nutrient supply from their own dead in an endless loop - that's why the max population (and CO2 production) tops out at an amount determined by how much yeast you add, rather than constantly increasing until the sugar is gone. With such a small amount of yeast, the nutrients may just be too sparse and diluted, leading to a "stall". You might try adding more yeast.

3) I use Fleishmann's "Active Dry" and lukewarm (body temperature) water. Only two failures - one described above, one when I skipped shaking the bottle. Anything fancier, including use of Prime or "proofing" the yeast, has proven completely unnecessary; although addition of 1 tsp. of baking soda does seem to extend production time slightly.

4) In a 2L bottle, bread yeast will die of alcohol poisoning before they can convert 2 cups of sugar. They're good for 1.25 cups guaranteed, 1.5 cups at best. Anything more is wasted sugar.
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This is what I do and it works perfect every time.

Put some duct tape around the top of the bottle cap making something like a bowl. Fill it with gorilla glue and let it dry (with your tube through the cap of course). The best bottles for me are Gatorade. I've had issues with soda bottle caps leaking air out of the sides. Gatorade seems to make a solid seal.
Maybe should have read more lol... probably bad yeast.
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