DIY CO2 not working

[Spaceman Spiff]

I'm using a gallon jug with the following:

2 L water
3 cups sugar,
1/2 teaspoon baking soda
1/4 teaspoon chamange yeast.

Nothing is happening. The mixture is 24 hours old and nothing is happening. No bubbles, nothing. The connections are fine.


Did I mix it too weak? Should I increase the amount of water and yeast? More sugar? More water?

Help please. ???

 

[Stephen Single]

I'm not sure of the effectiveness of Champagne yeast vs any other type of yeast.  They obviously all  do the same thing but the question is a matter of when they are most active (temperature etc) and how long and how quickly they are active.

I know in all of the co2 details I have read and written about they usually suggest bread machine yeast due to its rapid action.  Assuming the champagne yeast is ok...  Normally in mine I've done the following (I just started a new one 2 days ago actually)  I've normally used the rigid plastic flexible tubing.  I've used plumbing fitting reducers.  I've taken what is basicly the same size and threading as a garden hose which was reduced down and has a fitting in it connected to a short piece of rigid tubing, converted from that to another fitting that increase in size to fit one of those little knob handles they use on that type of rigid tubing (little round/thin handle through the valve) and it hooks to another piece of tubing and into a check valve to prevent back siphon (if it back siphons you will likely end up with yeast in your fish tank and that's not pretty I had this happen once when a check valve broke/wore out and it was bad...)  anyway.. then it goes into the tank into an airstone that bubbles into the filter inlet.

I then take the 2 liter.. put the mixture in it... wrap the top with teflon tape (about 10-12 times around) stick a hose washer in the brass fitting and then use channel lock pliers to grab onto the plastic that sticks out at the neck of the bottle.  Then I use pliers to tighten the brass fitting onto the threads of the 2 liter.

2 liters use a proprietary thread type that someone has a patent on or something and you will likely never ever find a plumbing fitting to connect to it.  The hose washer gets pressed into the top of the bottle between the fitting and seals 90% of the leakage.  The threads are wrong so since we are dealing with plastic vs brass the plastic loses.  It gets "bitten" into good by the brass and pulled in tight.  The teflon tape seals the rest of the leaks relatively well.

Why did I do all of that?  Because every time I used the aquarium silicone trick around the top of the bottle it leaked about a week into it.  I've tried every variation of silicone and caulks and rubber I could find and it all generally does the same thing.  If it did not do it the first bottle it did it the second bottle after you open it and put it back together again and a few days later it comes apart.

So your connection still may be suspect.  Try squeezing the bottle just slightly.  (Only if you left space at the top of the bottle.)  If you hear air around the bottle you obviously have a leak.   If it bubbles in the tank then you should be ok.  You need to leave about 2 inches at the top of the bottle at least.  I use 6 cups water to about 2 cups sugar and 1/4 tsp yeast (1/2 if it's past the expiration date and been refrigerated)  I know with bread yeast it starts to collect a "scum" at the top and bubbles start to form around the edges when it is working and producing CO2.  If you watch it you can see bubbles "appear" at the top every so often around the edges of the bottle.  After about a week it will turn clear in the bottle from the yeast brown and you will see bubbles streaming from the bottom where the yeast has collected.

I try to "spike" my yeast a bit by starting the mixture in 90-100F temperature water.  I let it sit for about an hour or two uncorked and then shake it a little again and then cap it with my fittings.

Normally within 4-8 hours it will start bubbling for me at that point.  At most it has taken 24 hours.  I also check the pH of my water and hardness as well before I start it and have it optimized per baking standards of water quality for bread making.  So this may have something to do with my rapid onset.

Regardless the "normal" method most follow will give results in as little as 24 hours and would take normally no more than 3 days to start bubbling.

I include the valve in mine to "slow" down the flow from full throttle and then as it gets older I open it futher to let more out.  It only has about 2% range usable for adjustment though since it was not designed for gas flow control so you have to be very very VERY light with the adjustments.

so 24 hours is a bit soon to say it failed.  But some of the above may apply as well.

 

[Stephen Single]

My message was too long... so I had to split it in half....


I have more information on CO2 systems on my website speaking toward the specifics of water quality and other CO2 related stuff.  I'm in the middle of building it right now actually so it will be growing if you want to check it and or stop back later and look.  it's at www.littlefishtank.com  Then there is a FAQ section with a co2 category.  I'm in the middle of building a navigation system for the FAQ database so for now it is just sorted in alphabetical order.  (CO2 is the first category so you are in luck I guess....)

I have recently started seeing people saying you need baking soda which I do not understand because backing soda needs an acid to get it going where water is not acidic.  Once you get the yeast acting it turns the water acidic and the baking soda kicks in with a vengeance and gives a quick burst from what I figure.  (Baking soda and vinegar as a kid in science class.... rapid burst of foam... no continuous reaction)  This may help a "slow" starting yeast to suplement it a little (low acid reacts with a little of the baking soda...more acid created by yeast...more baking soda reaction till it is gone adding co2 from the chemical reaction to the enzyme reaction?)

I say this with the acid thing because yeast is a plant which creates enzymatic reaction that takes sugar and converts it into a simple sugar that more enzymes react with and produce alcohol and co2.  (I have a FAQ on that as well for those interested in the technical end... )

Baking soda will not hurt I just think it's unnecessary...
3 cups sugar will make it last longer compared to my 2 because the limiting factor is the amount of yeast.. more yeast faster action and more co2 created but less time running till you need to make more.  More sugar means longer lasting.  Higher sugar to water ratio with more yeast means same lasting more co2... however too much sugar makes syrup...  that obviously will not work well.

Sorry so much on CO2... I just studied the heck out of it before I built my first one because I had to convince the significant other of the time that it was ok first before she let me do it in her house...  Then I bought a gas bottle and regulator and pH controller and powerheads and tubing and well..you get the idea...  I still use the DIY on a small 10 gallon I have though...  big bottle goes on the large euro bow front tank  I have...

I have a jungle in there....   CO2 is great stuff... I tested the tank without it with basic lighting and the plants died back.  I added power compacts into it and the plants sustained themselves and grew about 1/2inch to an inch every month at most... I added CO2 and the plants grew 5-6 inches every 2-3 weeks.  CO2 with basic lighting resulting in about 1 inch to 2 inches per month for most plants.  Some that only need low light levels on the other hand grew about 3 inches per month.  The ones that grow in low light well with the extra lighting grow about 8 inches per month now.

It's really amazing... that amount of plants and trimmings I throw out now.  When  I want a new plant I only buy 1 now (2 if really small and fragile)  and they grow like weeds.  I have plants that have leaves about 2-3 times larger than I've ever seen them in stores and other tanks.  I get plants that look messed up until I "trim" the lower half after they've grown for a few months and develop roots further up.  They are like 3/4 inch wide at the bottom and 2 inches or more across at the top on a single stalk...

 

[Stephen Single]

oh...  I just re-read you message again and noticed you said you were using a gallon jug.  I hope you've sealed the top really really well with some sort of rubber cork or something because milk jugs are not very air tight even with the lids they come with.   They will only hold fluid and barely do that.  They will leak gasses very very easily.

 

[Spaceman Spiff]

I checked everything this morning. The stopper at the top of the glass jug is a rubber stopper that I purposely drilled a small hole into. I then forced a stiff piece of tubing into it. I know this seal is fine.

I checked the one way valve fittings. They look ok as well. All the fittings look ok. Maybe I dont' have enough of the mixture in the jug. I can see the water level in the airline inside of the tank. When I blow into the airline, the airstone bubbles, but when I reattch it to the jug, the airline slowly starts to fill with water again (due to back pressure) and then once everything is equalized, it stops and continues to stay there. There is no leakage that I can tell. The jug is only 1/2 full and I think that the co2 that is produced isn't under enough pressure to flow into the tank.

 

[Matt Nace]

You can kill yeast if you don't bring it to room temp before adding the water. Then you only want to add warm water..never hot. My yeast(bread machine yeast) starts bubbling a foaming in a couple minutes.

I use 2 liter bottles hole drilled through the cap, place a hard plastic line through, use aquarium sealent on both sides of the cap. I let it dry and set overnight. I use a lot of it..and nothing escapes through that.

My yeast starts going up and you will notice it working it's way in in a few hours.
2cups of sugar and 1/4 tsp of yeast.

try blowing through the side that would be in the aquarium, leaving the other in the bottle. Then see if that rubber stopper holds your air in.

If that isn't the problem, test your yeast.

Bring some to room temp about 10 minutes. Get a cup of warm water, drop the yeast in. It should start to foam in a few minutes. If it does..you are ok..if it doesn't your yeast is no good.

Refrigerate after opening..and keep no more than 5 or 6 monthes.

 

[chooks]

I would change a couple of things maybe...  I would try to use regular yeast, it's cheaper and works a little faster.  You may also want to use a smaller container, that way you will be pressurizing less empty space.  Also, you might want to try a screw-on lid.  I know your system isn't quite working yet, but once it starts bubbling, it may pop out that stopper.

 

[Spaceman Spiff]

I had another look at the assembly today. The jug is producing CO2, but very, very slowly. I wet my finger and placed it over top of the output on the jug. The jug did offer some bubbles, but very few. The mixture in the jug doesn't foam at all. It looks like it's just sitting there.

I'm going to basicly double the mixture and see if that makes any changes. I think that there isn't enough back pressure from the jug to allow the CO2 into the tank due to the large volume of the gallon jug itself. Hopefully this will work.

Any other suggestions ?

 

[Stephen Single]

I would have to agree with the situation with the type of container used and the possibility of the stopper coming out.  Regardless of all that I normally only allow a few inchs at the top of a 2 liter... more specifically it's about 1/2 inch below the level soda comes in the bottle normally.  Also a 2 liter is designed for being pressurized where a milk jug is not.  I'd be worried of it "popping" if it blocks up in the tubing and leaking yeast all over (spraying/exploding)  

Definately fill your container higher but I'd really advise to switch it to something more pressure capable.

Someone has to have a resource comparing the properties of yeast...

hmmm I just searched for some stuff and found some kid you made a project for high school  that used yeast and some stuff for a device he called a gastrobot.  CO2 powered robot getting power from compressed gas from yeast reactions and stuff...  weird stuff....  however I have not found anything that really compared CO2 to links between one type of yeast vs another and how fast etc...

I did find this site in singapore I guess?  (url ends in .sg)  that mentioned champagne yeast saying basicly it lasts longer because it can stand higher alcohol content that kills most yeast but it is very expensive.  I assume it runs the same as bread yeast then for rate of CO2 production.  It can stand the hostile environment better.

http://www.ervine.per.sg/articles/diyCo2.asp

 

[Speedbird]

I've had more sucess by using bottled water (no chlorine) and warming it in microwave.  Also I change the check-valve every 6 months (I believe they harden and get pluged up a bit)  Keep trying, Have you ever seen those generic plants they sell at wall mart, look like bulbs you drop in and they "sprout" on a few weeks? with only a 24" full spectrum bulb mine will grow out of the tank and flower!
RGDS