# Possible Problem with my CO2 ?



## seltzerwater (Jan 20, 2010)

In my DIY CO2, a coke bottle passes CO2 to a filtration bottle of water, and then into the aquarium. I put an airstone at the end of the tube and buried it with some 1 inch size rocks. 

I can see the CO2 bubble go into the filtration bottle, but I can't see bubbles coming out in my tank. Either I'm having 100% diffusion or the bubbles are trapped somewhere and the bottle's gonna explode on me in the near future. I can see little bubbles around the plants but i don't know if that's because of the water change or the plants interacting with the CO2. How do I make sure my CO2's working and I won't have an accident >.<


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## Mikaila31 (Dec 18, 2008)

how long has it been setup for. It can take quite a while for the pressure to build up enough to force the CO2 all the way to the bottom of the tank.


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## cmc29 (Jan 10, 2010)

. Thats right it does take time to build up pressure, i always ran my diy co2 from the coke bottle though a powerhead, that was completely submerged and i could see all the co2 bubbles shooting out, you need to put a check valve on some tubing to keep it from backflowing


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## seltzerwater (Jan 20, 2010)

i have the bottles higher than the tank so shouldn't siphon. it's been running for about 5 hours now, still no visible bubbles coming out of the tubing >.<


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## cmc29 (Jan 10, 2010)

mine took longer than that to get going, it depends on how much yeast you use in proportion to the other ingredients. If you use more yeast it'll start quicker, bubble faster, and burn out quicker. If you have confidence in your recipe give it 12 hours or so, but keep and eye on it. You can feel the bottle start to tighten when co2 is being produced. My DIY always set below my tank and it worked fine. I installed a check valve in the tubing close to the powerhead, but i've never tried running it through an airstone.


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## seltzerwater (Jan 20, 2010)

i can see the bubbles in the filtration bottle, so I know CO2's being produced, but it's not passing from the filtration bottle to the aquarium even though I sealed everything up. I removed all the gravel and rocks and I see this happening in the tube -

The tube is submerged in the water, and water enters the tube to right beneath the surface. Every time a bubble is produced, I can see the water dip along with the bubble production, but it goes back to the same level, sort of like a heart beat. What could be the problem preventing the bubble from reaching the bottom. Is it possible the bubble is actually diffused into the water? Which I suppose would be optimal but I highly doubt it 

Thanks!


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## cmc29 (Jan 10, 2010)

I wish knew what to tell you. I never ran my setup like that. I'm sure someone on here will have some thoughts though. Good luck! As a side note: i just stopped running my co2 because i don't think it's needed, but that might not be the case with your setup, just a thought.


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## pete zahut (Feb 12, 2010)

if you shake the bottle with the yeast in it you'll see loads of bubbles, then if their still are no bubbles, it aint good.
it's better to have a backblow valve in the tube to your tank. I think that will solve your problem.
good luck!


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## seltzerwater (Jan 20, 2010)

when i put the check valve on and shook the bottle a lot, bubbles came out, but when left normally no bubbles again...is the check valve faulty? thanks!


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## pete zahut (Feb 12, 2010)

you can test the valve by just blowing through.
just wait for a few days, it won't explode or anything becouse it is working, but maby not perfectly.
did you add enough sugar?
hope it works, refilled mine this morning, it smelled like very, very cheap beer 
greetings


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## nomel (Jul 20, 2009)

Not sure if this was mentioned, but since you're into DIY, you should look into building a co2 diffuser. The amount of co2 that can be absorbed by the water in the time that it takes the bubble to go from the bottom to the top of your tank is pretty small. A diffuser recirculates the bubbles around and around, allowing nearly complete absorption.

Lots of good vids of DIY solutions working on youtube...I like the kind made from glass. They can be anywhere in your tank, even near the surface a little more out of sight, unlike most in the vids which are on the bottom.
YouTube - co2 diffuser diy


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## pete zahut (Feb 12, 2010)

nice, you can also buy them on ébay for a few dollars.


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