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Turnng off the diy c02?

1127 Views 11 Replies 7 Participants Last post by  [email protected]
just a quick question.
im thinking of making my own DIY c02 system fo my 20 gallon tank.
ive read on the internet how to make them from air tubing and a 2 litre coke bottle....
but if thats all it is how can it be turned off at night?
if left on it wud kill my fish correct?
if i was to pull the tubing from the bottle or out my tank then the c02 will be wasted right?
people have told me its best to turn the c02 at night but how?

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I run my 2 diy co2 sytems in my 55g and my 15g long 24/7.
I use 2 two litre bottles in the 55g with no issues from either set up.Most
people will tell you that diy co2 put an amount that will have your fish gasping for air.
Some links:
pics: co2 gas seperator &fr2=tab-web&fr=moz35
I run two 2L bottles on my 20 gallon tank. I have a spray bar that causes a very slight surface agitation. Prior to this, I had an airpump set on a timer to come on when lights go off because my fish would be gasping at the surface without it.
Using 1 bottle on a 20 gallon wont cause that.
I use a 2 liter bottle and gas separator/ bubble counter on my 15g long with no gasping issues.Fish may start to gasp when there is a lack of oxygen in the tank also.
Timer+airstone=no co2 during the night
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With one DIY CO2 bottle on a 20g tank, it won't be possible to gas out your fish. Or with 2 bottles. If you have a HOB filter, 5 bottles *probably* wouldn't do it. You can leave it on all night with no worries.
i dont have a "hob" filter....i have a corner filter which came with my juwel tank.
however i do have 2 filters running in my mounted above the water surface and one thats submerged...this ok with a single c02 bottle?
i certainly wont be using 5 bottles :O
im only planning on using 1...maybe 2 at most.
thnx for the help
The point i was trying to make with the Hang On Back (HOB) filter was that if you have something creating water turbulence, CO2 will leave the water even faster. 2 DIY bottles will not harm your fish running 24/7.
What some of the guys are trying to tell you is that having a source of surface agitation will cause the co2 in the water to out-gas. Sometimes this is good, sometimes this is bad. During the day when the lights are on, you want to keep the co2 in the water, so any filter or airstone that's running can potentially disperse any co2 you add to the water into the atmosphere, which is bad. At night when the lights are off and the co2 could potentially build up and harm your fish, this is good. I have my canister filter on a timer offset from the lights. For 9 hours a day, the lights are on and the canister is off, at night they switch. This keeps my co2 up during the day, and down during the night so that I don't have to mess with it too much, other than to check the diy co2 bottles for a decent output. When they start to slow down, I mix up a new batch. Currently running two bottles, each with a checkvalve so that when I take one off to mix a new batch, the other one keeps the bubbles going.
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ok, thanks for the help guys. :) i have to use one of these?
i was simply just going to attach the air tubing to the bottles and straight into the tank itself with nothing else attached to the air tubing i.e. check valve's ect ect.
if i wer to use a check valve, how do you use it? when setting up diy c02?
wer does it go?
I would recommend a check valve, it's cheap insurance. I actually use 3 of them at the moment. One going into the tank at the top, and one on each bottle of diy co2. That way I can unscrew one bottle without depressurizing the whole line, only the one that is open gets blown out. The other bottle keeps on bubbling. Just looked for my camera, and it's at my buddies house where I'm building my new stand and hood for my 29g setup. I'll try and add some pics when I get back over there.
A check valve is very cheap insurance.

Before you toss your next worn out solution, waft some of the aroma towards your nose. Don't breath from the bottle.
Now consider that aroma permeating a rug, carpet, cement or wood floor that "belongs" to a significant other. Wife, mom, landlord, etc.

Check valve = $2.00 - $10.00
Professional cleaning of flooring = big $
Loosing the right to have an aquarium, unless you're single, = priceless
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