DIY CO2 Not Working!

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Satsumas

Aquarium Advice FINatic
Joined
Jan 29, 2005
Messages
610
Location
Cambridge, England (UK)
Last night i rustled up a mix it was 2 cups of sugar with 1/2 teaspoon of yeast. Firstly i poured a cup of sugar into the measuring jug then added 1/4 teaspoon of yeast, with some luke warm water stirred it with a spoon and poured into the bottle. I done the same again and topped the bottle off until 3/4 full with luke warm water.

I looked this morning to see if some bubbles were going into the diffuser but there were none. I then shook the bottle and still nothing, just a minute ago i shook the bottle again for about 10 seconds and still nothing.

This is the first time i have made a 'double bottle' CO2 injection so i'm thinking that maybe there's a problem somewhere with the tubing etc...

Does the mix and everything sound ok so far? I can't see any problems but i'll go and check the whole system.

TIA
 
You are using check valves? If so, check to make sure they are installed in the proper direction. Could you just have bad/old yeast? Place some in a bowl of warm water and see if it will start to grow.
 
If your using check valves (and you should) make sure they are placed properly or you could have a messy explosion on your hands. It could also be old yeast. You can proof yeast by dissolving it in a small amount of lukewarm water with a little sugar. It should start to foam within 10 minutes or so. If it doesn't then it's probably dead.
Make sure you have no leaks in the system. This could also prevent the CO2 from making it to the diffuser.
 
At first i thought that the check valve was the wrong way round but i blew threw it and this time there were bubbles!

I just done the yeast check and it seems to be fine, there's just a yellowish pool in the bowl next to me which stinks! :lol: The yeast seems to have dissolved.

One other thing i think may be a problem is the journey in which the CO2 will have to make. It's long and a little bit bendy, in my other tank it was'nt such a steep climb either.
Should i try and make the journey a little easier? I could cut any excess tubing off but that's about it.
 
In a small bowl the yeast shouldn't be a yellowish pool. It should be actively foaming. You should see bubbles forming and foaming up. I suspect that your yeast is dead. Buy soem fresh yeast and try again if it doesn't work then there may be another issue.
I also noticed you fill you bottles 3/4 full. This may be a little low. I usually fill mine to just below the shoulders of the bottle.
 
Ahh, yes then i suspect that the yeast is dead. Highly annoying as i just recieved my order of HC, Bacopa C, and ferts. Also i only got the yeast yesterday after continually nagging for some for weeks!

Now i dont really want to put the plants in there with no CO2 or ferts because i'll just get algae growth again! So what do i do with them? At the moment the Bacopa has been seperated, taken out of the rockwool and is sitting in a plastic bowl of tank water.
The HC is still in the pot sitting in tank water. I suppose i could leave them there for a day with no problems but any longer and they'd start to deteriorate, so i'll try and get hold of some fresh yeast tommorow. How do i know if it's fresh or not? (Potential stupid question no doubt)
 
Here's what I do when I change out a bottle.
I take 2 cups of sugar and add 1 tbsp of molasses. I then add 1/2 bottle of water and heat it until all is dissolved.
I then add the other 1/2 bottle of cold water. This usually leaves me with a temp of about 90F. (perfect for yeast).
I then place 1/4 tsp of yeast into my bottle and add about 1/2 cup of the sugar mixture. I let this sit for a good 15 minutes and then check it. If the yeast is alive there will be foam on top of the solution and it will have that fresh bread kind of smell. It shouldn't smell bad at all if anyhting it should make you hungry. I then add the rest of my sugar solution up to the shoulders of the bottle and cap it. I then attach my hoses and I'm good to go.

I should add that when I use the bottle to measure the water I take into account that the sugar takes up asignificant amount of space. So, I fill the bottle up 3/4 of the way before making my solution.
 
The recipe I'm using that works within minutes is:

a Fresh packet of yeast, 2 cups of sugar, water, 1/4 tsp of baking soda.

Add 2 cups of sugar to the bottle, add water until 2/3 full (slightly warm). Add the baking soda and 1/2 tsp of yeast. Now, I'm not sure if this makes a difference or not, but I do not mix or shake it at all. it's layered and the yeast responds instantly. I've had 2 weeks now of 30-40 bubbles a minute!!
 
I also know you should make sure the bottle has been sterilized first. Any bacteria in there and the yeast will be no good. I have heard of people using boiling water to sanitize the bottle prior to filling it, and then adding the ingredients after the bottle has been allowed to cool a bit.
 
That's not necessarily true. You do not need to sterilize the bottles for yeast to work. Yeast works quite well with other bacteria and is bacteria itself. Yeast creates an acidic environment on its's own that prevents what may be harmful organisms from gaining a foothold. The bottles just need to be rinsed in hot water without soap very well.
Remember the mixture inside the bottle is not going into the tank just the CO2.
If the bottles start to look a little grungy then you can always switch them out for new ones.

It's the combination of wild yeasts and other bacteria which give us sourdough breads.
SEE MOM, that culinary school education paid off!!!

As always this is my opinion and all may feel free to disagree
 
For baker's yeast and granulated sugar, if you're using more than 1 cup sugar for every 3 cups of water, you're probably wasting sugar.

I've done the math here - 23% v/v sugar in the initial mix will get used up by the yeast just as the EtOH reaches lethal levels (>10%).
 
Best Before End 05' :roll:

Someone at the shop should get a little pink when they see that there selling something that is 2 years out of date! Good job the reciept wasn't thrown out.
 
Just wanted to point out that yeast is a type of Fungi, not bacteria. :D

With my DIY CO2 mixtures, I dissolve the sugar in warm-hot water before adding the yeast. I only put maybe 2 cups of water in with the 2 cups of sugar and shake the bottle really well to dissolve the sugar. Then I add more water (until it narrows at the top) and add 1/4tsp of yeast. The second time I add water, its lukewarm-cool. Then I gently shake it again and I'm good to go. This usually gives me really good CO2 production for about 3 weeks, then it slacks off a bit, so I try to change 1 bottle out every 2-3 weeks.

Hopefully having some unexpired yeast will make yours work! Good luck!
 
I think we all have our own personal recipes that work for us but the main thing is we are using the freshest yeast available.
 
Tepid water, not lukewarm is recomended for yeast. Tepid is neither warm nor cold..it is neutral feeling.

If your tap water has chloramines, it may help to use some declorinator.

If the room temperature is too cold, or the yeast bottle is sitting on a cold surface, then the yeast my not perform.

Unused yeast should be stored inthe freezer, and then allowed to come to room temperature before use.

Yeast also like some molasses, or protein drink to help them grow nicely.
 
Please note that it can take upto 24 hourse for a batch of yeast to get going. If it's in a cold room it will take longer than when in a warm room, and production will be much slower. Placement of the bottle and the length of the tubing can make a difference in out easily the CO2 makes it into the tank.
 
Thanks for the advice! This thread realy is a good read. I'll have to give this a try.
 
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