DIY CO2 problems

[Lenna]

I recently decided to set up a DIY CO2 system with the 2L coke bottle, sugar and yeast. I can get it working wonderfully, but it only seems to work for about a week before it stops releasing gas (will still bubble if I squeeze the bottle). I followed the instructions given in a post made on here. It said 2 cups of sugar should last approx. 2 weeks. What am I doing wrong?

 

[The Mohave Kid]

I don't know .. never used one before ... but brewed beer many times

Based on what little I know of fermentation the following could be worth checking out ...

1. Temperature --- this will effect the rate of fermentation. At warmer temps you might be getting a burst of CO2 ... 65 -70 F is the slow end of most yeast.
2. More sugar perhaps is all you need ... but
3. Alcohol will build up and shut down fermentation by killing yeast so that might work against you ... Get a bigger coke bottle ?? .. two Coke bottles .. Connected ?
4. A touch of Magnesium salts can help ..

I wonder what kind of yeast you are using ... if I remember correctly some yeast may tolerate a bit more alcohol ... or I might be making that up .. can't remember.

Good Day ... B)

 

[Angry_Platy]

I am using 2 coke bottles joined together with tubing....with 2 cups sugar in each bottle and 1 and a 1/4 teaspoons yeast per bottle (I am fiddling with the yeast amount a bit atm).....last week I used 1 teaspoon of yeast per bottle and it only lasted 5 days.....I tried reducing the yeast and it only lasted 3 days...so I now have increased it. I will keep fiddling with the recipe till I get 2 weeks of bubbling out of it.

I think it is a personal thing depending on the ambient air temperature, the type of yeast you use and the initial temperature of water you use to dissolved the sugar and yeast.

I will let you know how I get on

 

[Yenko]

I use bakers yeast and get 1-2 weeks useful life out of my bottle. I'm only running CO2 on a 10 gallon tank, and because the consumption is so low even a very low rate of fermentation is acceptable; when I prepare a new bottle 80% of the CO2 is wasted by the hole I put in my bell jar to control the level of gas in it.

 

[andywg]

I recall reading that Champagne Yeast can offer a long time (up to 4 months) before alcohol kills it (this is the reason why most DIY CO2 stops). Though it costs quite a bit more.

 

[Lenna]

Yeah, it's probably the temperature. It's pretty hot here so I guess it's just growing too quickly and running out of sugar. Is there some sort of buffer I could add to reduce the effects of the alcohol?