# Problems with CO2 yeast reactor - need help



## CatG (Apr 10, 2010)

I've only had my tank set up for a couple of weeks, and I have had nothing but problems. I'm new to this, so I have made mistakes, followed bad advice, etc, but I AM trying to do things right.

I have a 75 gallon long tank with several plants in it. A couple days after I set up the tank, I added 3, 2 liter yeast reactors. Things were going along fine, with CO2 levels at 31ppm. Until this morning. I noticed that the bubbles were down to only one every couple of seconds (was working fine yesterday). My levels dropped to 11 ppm, and my PH went up from 6.5 to 7. I figured the bottles needed changed, so I rinsed them out and added more sugar, yeast and water. It's been 3 hours and I still have no CO2. The first bottles were producing CO2 within about 15 minutes. My fish are acting funny, and I'm guessing the PH swing is not to their liking.

I disconnected all the hoses and none of them are blocked. What could be wrong?

Frustrated,
Cat


----------



## Big_Fish (Mar 10, 2010)

Hi, Cat... 
I'm actually surprised your first bottles began putting out co2 in such a short period of time... did you use active dry yeast?
that typically takes close to 24 hours before it begins putting out enough co2 to overcome the weight of the water in the tank. (it takes the dry yeast a couple hours to hydrate and multiply)

one thing you can do right away to at least spped things up as much as possible is to get the temp of the yeast mix into the 78-90F range: fill a saucepan (or a bucket, whatever you have) with HOT tap water and put the yeast bottle in there to bring up the temp. the yeast will multiply much quicker.

you can also use this same technique when co2 production slows. (people often use the bucket technique permanantly... with a submersible tank heater)

it also helps to NOT rinse the old bottles out... leave half a cup or so of the old mix and just add yeast, sugar and water.
yeast mix is SORT of like the beneficial bacteria we all know and love... it takes a while for them to build up their numbers, but once they do... it's good not to kill them and start all over. 

I have a couple of posts floating around here on the subject.... I'll find em.


----------



## Seattle_Aquarist (Mar 7, 2008)

Hi CatG,

I used to only change one bottle at a time, one bottle about every 3 - 4 days. In the cooler weather, my bottles put out less in the morning that in the evening because they would get cool overnight (when we turn the heat down when we go to bed).


----------



## CatG (Apr 10, 2010)

Yes, I used dry active yeast.

It's been over 24 hours, and still no CO2.  I am going to empty these and start over - hopefully that works because I just bought a bunch of plants and ferts. If not, I don't know what to do. I can't spend any more money on this for at least 2weeks.

Cat


----------



## Big_Fish (Mar 10, 2010)

Hi, Cat...
ARE YOU USING A GLASS/ CERAMIC DISK DIFFUSER?
(if you are, forget everything below and remove the glass diffuser. you should see bubbles immediately)

they can be difficult to troubleshoot... my apologies if I'm asking dumb questions.. 
it's gotta be either that the yeast mix is not producing, or that there is a leak in the system.

are the bottles connected to each other, or do you have individual air hoses going into the tank?

are you using a check valve of any kind? (they can get sticky/clogged)

if the mix is producing Co2, you will be able to see tiny bubbles rising to the surface in the fermenter bottles.

http://www.aquaticplantcentral.com/forumapc/diy-aquarium-projects/70412-diy-co2-questions-3.html

post #27 on that page has a decent step by step on starting a new batch.


----------



## Seattle_Aquarist (Mar 7, 2008)

Hi CatG,

I occasionally had problems with the mix not working if I used water that was too warm. Apparently if the water is too warm it "kills" the yeast.


----------



## CatG (Apr 10, 2010)

Thanks for the replies!

Yesterday, I emptied my 3 bottles and replaced the mix. Still have no CO2 going into the tank this morning. However, I DO have tiny bubbles being produced in the bottles. I'm guessing I have a leak in the system.

My system consists of 3 bottles and hoses hooked up to 2 T valves, finally converging into one hose which goes into the tank, and is inserted in the filter basket on the intake tube. Today, I am going to hot glue the tubes in the tops of the lids in case the leak is there. The T valves, which are cheap, could also be the problem. While removing the hoses yesterday, the pieces you connect the hoses to (sorry, don't know what they are called) kept pulling out of the plastic T valve. I will see if I can find better T valves and replace these.

Thanks again for the help! I never thought to check for bubbles in the bottles (makes perfect sense, I just didn't think of it), so now at least I know it's not the yeast mix that's failing.

Thanks again!
Cat


----------



## Big_Fish (Mar 10, 2010)

Hi, Cat.. that link I posted also has a good run through on leak checking... I don't like the hot glue gun trick, I tend to get the glue where it doesn't belong, or worse: melt a hole through the tube with the gun. make the hole in the bottlecap SMALLER than the tube. the tube becomes the seal.
soapy water mix dripped onto the connection will reveal any leaks.


----------



## CatG (Apr 10, 2010)

I used a drill bit smaller than the tube to make the holes, but it's still possible it's leaking there. I will check it and see. If it is leaking, I will try some silicone (can't find my hot glue gun anyway). If the silicone doesn't work, I will buy new bottles and drill new holes. I will also check the T valves to see if they are leaking. 

If I get soapy water into my yeast mix, will I have to mix up a new batch?

Thanks,
Cat


----------



## Big_Fish (Mar 10, 2010)

CatG said:


> If I get soapy water into my yeast mix, will I have to mix up a new batch?


Nope.  
if a little does manage to get in, it won't hurt anything.
(don't disassemble anything while leak checking)
also the system is pressurised... c02 pressure should keep anything out.


----------



## CatG (Apr 10, 2010)

Ok, changed the mix again yesterday and siliconed around the hoses in the lid (inside and out), checked all the hoses again and none of them are blocked, all 3 bottles are fizzing, and STILL no CO2 getting into the aquarium. I am still going to try a few things, but I am really at a loss as to what could be wrong.

I am going to do a leak test today with the soapy water, but if I can't find anything wrong, I am not sure what to do. It seems odd that all was working fine for almost two weeks, only to wake up one morning and find it wasn't working. You would think that depleated yeast mixture was the cause, but that was the ONLY thing I changed. Nothing else got touched - I simply removed the caps to the bottles, refilled them, and put the caps back on.

Anyone have any ideas whatsoever? Assuming there are no leaks (which I will test for today), knowing that the yeast mixture is producing bubbles, and knowing that none of the tubes or T valves are blocked, what in the heck could be the problem?

If I can't get this figured out, what is the absolute cheapest way to make a pressurized cannister fed CO2 system? I don't think I will need any kind of gauges since I can test for CO2 levels, but I will probably need something that regulates the flow of CO2 so I can control how much is going in. Any advice or recommendations for products would be greatly appreciated.

Thanks,
Cat


----------



## CatG (Apr 10, 2010)

Well, the soapy water test revealed no leaks, but we ended up finding a small leak in one of the lids by blowing through the hose and listening carefully for air escaping. Plus there was water in some of the lines, which we cleared out. After all of that, it started working again! Sheesh, what a pain in the butt THAT was. 

I found a CO2 cannister (with some CO2 still in it) and a regulator on Craigslist for $50. Is that a good deal? Would I need to buy anything else to make it work, or can I just attach an air hose and stick it in the intake tube of the filter?

Thanks,
Cat


----------



## Big_Fish (Mar 10, 2010)

Hi, CatG.. 
Heck, I spent $50 on just the empty canister....
(and that was a great deal)
what's the brand of regulator/post a pic if you can... 
assuming the thing works/doesn't need to be fixed that's as good a deal as I've seen in a while.

yes, you can stick the co2 tube in the filter's intake tube, (that's where you have the diy Co2 tube going now?)


----------



## CatG (Apr 10, 2010)

It says it's an Eheim regulator, but I'm not sure what size the bottle is. She said it worked when she took her tank down a couple of years ago, but hasn't used it since. I am posting a couple of pics.

And yes, I currently have the air hose from my DIY CO2 going directly into the filter basket on the intake tube. That got me from about 12ppm (when I simply had them all hooked to their own airstone) to about 31ppm. I'm glad to hear I can do the same thing with the CO2 bottle because that way I don't need to buy more equipment. lol

Cat


----------



## Seattle_Aquarist (Mar 7, 2008)

Hi Cat,

That definitely does not look like DIY CO2......LOL! I see a tank (about 10# steel) and the regulator and gauge. Did it come with a needle valve too? It would go between the output of the regulator and your tank. It may actually be screwed into your regulator. Can't tell from the picture.


----------



## Big_Fish (Mar 10, 2010)

I googled Eheim regulator and found yours on craigslist... 

you MAY need a needlevalve for that one, everything I've discovered so far about that regulator mentions an 'adjustment screw' (besides the mail Shutoff valve) but little other info.
(the needlevalve is the fine adjustment for the amount of CO2 sent to the tank) ... 

the only other thing I'd want to confirm is how old the co2 canister itself is. (they're good for at least 10 years... but I'm NOT positive what happens after 10 years... remanufacture perhaps) the date is stamped right on the bottle.


----------



## CatG (Apr 10, 2010)

Well, I emailed the lady about the age of the tank, and she said she didn't understand the numbers so she couldn't tell. I sent her some pics of paintball tanks with their numbers described, hoping this was similar to her numbering, but she said her numbers weren't like those. She started to get kind of testy about answering the age question. I don't think I asked anything that should have made her mad, and I didn't mean to if I did. Not sure why she started acting like that because she was really friendly in the previous emails.

Oh well, I will keep looking.

Thanks!
Cat


----------

