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DIY CO2: Effect of bottle size?

6778 Views 9 Replies 7 Participants Last post by  Florida_Larry
There are posts for DIY CO2 using bottles from 10oz, to 1L, 2L, or even 1 gallon. Just what difference does the size of bottle make?

If I put 1.5cups sugar, 1/2tsp yeast into a 20oz, 1L, 2L, 1G bottle and fill 3/4 full of water the only difference will be the concentration of sugar in the water. Which bottle size will yield the most appropriate sugar solution for yeast? Has anyone done an experiment to compare?

Personally, months ago I tried using a 2L bottle, but the yeast did not seem to take. After several attempts I tried a 20oz Powerade bottle which did great. I have not tried any other sizes.

Is there some data one this?

--Thanks.
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a good question, and one i have wondered myself. Like you i have made a few differant configurations, 1/2 tsp, 1/2 pack, 2 cups sugar, 6 tblspn grape jelly, Bakers yeast, Brewers yeast, etc etc, all or course in a 2 litre bottle and paired 2 litre bottles.

best results so far is a single 2 litre bottle, lukewarm tap water, 2 cups sugar, 1/2 tsp bakers yeast. lasted approx 3 weeks.
raised my CO2 in my 55 gal to just over 9%. Very good plant growth resulted.
Two bottles did not increase the time it lasted only increased the amount output.

Next trial is 1 gal with same sugar / water concentration, but volume increased to match 1 gal. and yeast stays the same as 2 litre bottle.
Should yeild same output, just go longer. I Hope. Someone else want to jump in here and take a wack at the One Gallon? or has tried a one gallon with lower Yeast?
i use 1 gal. juice bottles because they wont easily tip over, have handles, and imo hold more water which makes the alcahol content stay lower for longer periods of time keeping the yeast alive longer.
I would think the only restriction is that at a certain point you will reach a sugar concentration high enough to inhibit yeast growth(think jellys and preserves) or that the alcohol concentration will rise to lethal levels faster.
I have used a trio of 40L plastic jerry-cans with 9Kgs. of sugar, 1L of molasses and 1 teaspoon of bread yeast and 1 teaspoon of local hooch yeast in each (filling only one every week on Saturday). I obtained a very steady supply of CO2 enough to get a 240G, a 145G, and a 60G heavily planted high lighted tank pearling to glory. Then I must also tell you that the night production was also retained by my system and used during the day.

My local hooch man (the sponsor) was quite satisfied with the byproduct. :)
Personally, months ago I tried using a 2L bottle, but the yeast did not seem to take.
How long did you give it to get going? I recently had some frustration when replacing my used up DIY co2 2 liters, where I was sure the new 2 liters had failed somehow and weren't going to start. I just ended up getting frustrated and leaving them connected with no output to my work tank for the weekend. I came back to find them bubbling away as normal. Sometimes it can just take longer than you would expect for the mixture to really get started.

EDIT: FYI, the mixture I'm using now with satisfactory results in 2 liter bottles is:

2 cups sugar
1/2 tsp baking soda
1 tsp protein powder
1/4 tsp wine yeast
Dechlor or distilled water

I also activate the yeast by placing in a cup of very warm water with a pinch of sugar, and vigorously stirring up the water every 30 seconds to a minute for about 5-10 minutes before adding to the mixture.
i use 1 gal. juice bottles because they wont easily tip over, have handles, and imo hold more water which makes the alcahol content stay lower for longer periods of time keeping the yeast alive longer.
what kind of run time are you getting out of your 1 gal mix?
curiosity got the better of me, i have started a 1 gal mix tonight
4c sugar
1/2tsp bakers yeast
1.5 tsp protien

3c sugar water mix with 1L of heated water until dissolved
added remaining sugar and topped jug to 3/4 full using room temp water
Yeast added to luke warm water w 1/4 tsp sugar to start it.
leave sit for 5 min. than add to mix above.

1 Gal jug feeding into a .5l seperator ( water bottle ), with water in bottom( serves as seperator and bubble counter). then to tank using a regular air diffuser.

Now we will see how long it takes to "start"
Then how long it lasts.

If it seems to work well (generating CO2 beyond 6 weeks ) , i plan on trying a second version using Grape Jelly instead of sugar.

Updates:
@ 2 hrs after setup Bubble rate - 1 / 59 sec
@ 12 hrs after setup Bubble rate - 1 / 1 sec
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i found a 3 gallon bottle and i plan to use teh same yeast i would use for a 2 liter bottle but much more sugar like 10 o 12 cups of sugar bu t my question is that i have been readin your post and what protein is that you use what its for and where can i get it

thanks
the protein is not needed, it supposedly increased the food available to the Yeast. However it is Glutamin (sp) Found at GNC etc

Will be interesting to see how long a 3 gallon goes, lets see 2 cup/s litre i used 6 cups in my 1 gallon so your going to be looking at roughly 18 cups
sugar.
Where did you find a three gallon container to use?


start of week 2 bubble count is 1 bubble every 1.9 sec
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