# How long would a 20oz co2 tank last?



## Daximus (Oct 19, 2011)

KenRC51 said:


> I plan to get this co2 tank for my Mr. Aqua 17g.
> http://www.amazon.com/Pure-Energy-2...2WAW/ref=sr_1_1?ie=UTF8&qid=1328065277&sr=8-1
> 
> How long would this tank last before I need to refill? *I don't know how much co2 I would be releasing* but just like to know an estimate on how long it would last.


Neither do I. Impossible to answer your question with any degree of accuracy. 

A guess...mmmhhhmmmm, 4-6 months on a 17 gallon.


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## livingword26 (Oct 28, 2010)

Depends on your plant load lighting and co2 diffusion method. I use up 5 lbs a month with my 29 gallon.


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## Sethjohnson30 (Jan 16, 2012)

I have mine at 4 bubbles per sec it's a 20lb and I have only filled it once, that was a year and a half ago( I have it on a timer so it's only on 12 hours a day)


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## kevmo911 (Sep 24, 2010)

livingword26 said:


> Depends on your plant load lighting and co2 diffusion method. I use up 5 lbs a month with my 29 gallon.


A 20oz cylinder on a 17g, assuming you have a solenoid, might last a couple months. But on a 29g, going through a 5lb cylinder in a month? Big, big leak.


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## KenRC51 (Oct 13, 2011)

I think I'm gonna get a a 5lb instead of the 20oz tank. Thanks for the feedback, without the members help here I would have went and bought the 20oz tank.


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## qxz06090 (Jul 5, 2010)

i have 20 gallon fish tank and 20oz. paintball set up. since is close size i think you co2 should run 3 or 4 month for maxium.


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## galabar (Oct 19, 2011)

I've got mine at about 1 bubble every 8 seconds in my 40 breeder. I bubble it into the intake of my Rena Filster XP2. My 20 oz cylinder has lasted "a long time" so far. I haven't been keeping track.

I think the most important thing when dealing with low bubble rates it to make sure there are no leaks. Even a small leak will cause you to empty out your cylinder months before it would otherwise when you have a low bubble rate.


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## Dave10910 (Nov 8, 2011)

Yeah if you make sure that there are no leaks it'll definitely last longer. If an efficient reactor is used a 20oz tank might just last 3 months or more. Overall though a 5# or even a 20# is much easier in the long run and will last quite some time on an aquarium that small.


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## psalm18.2 (Oct 16, 2010)

How about in a 55G using DIY on the other end? About a week tops?


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## hbosman (Oct 5, 2006)

I used to use a 20 OZ cylinder per month on a 46 gallon with an inline diffuser. CO2 ran 8 to 9 hours per day. You will be much happier with a 5 lb though. That's what I use currently.


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## livingword26 (Oct 28, 2010)

kevmo911 said:


> A 20oz cylinder on a 17g, assuming you have a solenoid, might last a couple months. But on a 29g, going through a 5lb cylinder in a month? Big, big leak.


5bps 24 hrs a day. If there is a leak, I can't find it.


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## ktownhero (Mar 21, 2011)

livingword26 said:


> 5bps 24 hrs a day. If there is a leak, I can't find it.


5bps 24/7 on a 29g? That sounds incredibly inefficient. You should be able to go at least 3-4 months with 5# tank on a 29g, I've heard of people even going over 6 months.


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## KenRC51 (Oct 13, 2011)

How do you know if you have a leak? I know you can spray some water on the connector area and see if bubble comes out. Does it smell like propane?


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## Dave10910 (Nov 8, 2011)

KenRC51 said:


> How do you know if you have a leak? I know you can spray some water on the connector area and see if bubble comes out. Does it smell like propane?



Use soapy water. You should be able to see it bubbling. I've never had a problem using this method. 

And no, I don't believe it should smell like propane. Never heard of that. Maybe something more serious going on there?


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## ktownhero (Mar 21, 2011)

Yikes, Ken, you aren't supposed to be injecting propane into your tank!


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## galabar (Oct 19, 2011)

livingword26 said:


> Depends on your plant load lighting and co2 diffusion method. I use up 5 lbs a month with my 29 gallon.


First, what is your diffusion method? You mentioned 5 bps. That seems like a lot for a 29 gallon (I'm using 0.125 bps on a 40 gallon). Even at 5 bps, you should be able to go for several months with a 5 lb cylinder. You should shut off both your CO2 cylinder and regulator and close your solenoid and/or needle valve. Your gauges should hold steady for several hours. If not you have a leak.


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## galabar (Oct 19, 2011)

KenRC51 said:


> How do you know if you have a leak? I know you can spray some water on the connector area and see if bubble comes out. Does it smell like propane?


You are using a CO2 cylinder, right? That should be odorless.

Here is a reference for testing leaks:

http://www.plantedtank.net/forums/equipment/137245-complete-leak-check-co2-pressurized-system.html


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## KenRC51 (Oct 13, 2011)

Dave10910 said:


> Use soapy water. You should be able to see it bubbling. I've never had a problem using this method.
> 
> And no, I don't believe it should smell like propane. Never heard of that. Maybe something more serious going on there?





ktownhero said:


> Yikes, Ken, you aren't supposed to be injecting propane into your tank!


I don't have a co2 tank yet but will be getting one. I know I'm not suppose to put propane in a co2 tank, its for co2. 

I never smelled co2 before from a co2 tank so I don't know how it smells. They probable don't have a smell. Just bad breath smell form the co2 we exhale, lol


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## Naekuh (Oct 19, 2011)

man i got ripped off for the first time at a paintball store.

A girl filled it for me... but as i was watching her, she didnt weight it. 
I then took the bottle and shook it, no sound nothing off a 24oz paintball tank.

Correct me if im wrong but a filled tank should be at least 33% liquid co2, which means if u shake it, you should hear noise... no..

I asked her if she was sure its filled and she said yes, i told her i hear no liquid, and she said ur not supposed to... i gave her a wierd look and told her there should be liquid CO2 inside, and she offered to weigh it.

I was in a rush so i opt'd not to weight it... i guess she felt bad so she gave me a discount on the fill, but seriously guys... i cant stress enough.. 

ALWAYS ASK THEM TO WEIGHT IT....


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## livingword26 (Oct 28, 2010)

galabar said:


> First, what is your diffusion method? You mentioned 5 bps. That seems like a lot for a 29 gallon (I'm using 0.125 bps on a 40 gallon). Even at 5 bps, you should be able to go for several months with a 5 lb cylinder. You should shut off both your CO2 cylinder and regulator and close your solenoid and/or needle valve. Your gauges should hold steady for several hours. If not you have a leak.


diffuser method is a cheap ceramic diffuser inside of a Rexx Grigg style reactor. The reactor is short, and only dissolves abotu 60-70% of co2, which puts a fine mist in the tank, which is the way I like it. The regulator set up has all been soaped up for leaks.


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## TopShelf_Symbiosis (Apr 11, 2013)

How long might a 20oz last on a 9g tank?

I am not sure at what bubble rate I would use, but lets just say 6 per second.


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## Big O (Jun 28, 2011)

TopShelf_Symbiosis said:


> How long might a 20oz last on a 9g tank?
> 
> I am not sure at what bubble rate I would use, but lets just say 6 per second.


my 20 ounce tank last 2 months at 2 and a half bps, on a 29 gallon.
and my plants are very healthy.
hope that helps,

big o


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## assasin6547 (Feb 6, 2013)

How long would a 50lb last on a 10 gallon?


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## UDGags (Sep 13, 2009)

assasin6547 said:


> How long would a 50lb last on a 10 gallon?


6 yrs..lol....

20lbs on my 125 gal lasts 2.5 months

Sent from my DROID BIONIC using Tapatalk 2


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## mwuf15 (Aug 3, 2010)

my 5lb last around 8-10 months on a 60gal. 50lb would last a really long time on a 10gal.


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## sepulvd (Mar 19, 2012)

my 20oz tank on a 10g around 1bps so far have used half a tsnk in 3 months


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## JAYGEE (Apr 2, 2013)

Just picked up a 20 lb for my 12g long. Hope it lasts a year or more @ 2bps


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## TexasCichlid (Jul 12, 2011)

livingword26 said:


> Depends on your plant load lighting and co2 diffusion method. I use up 5 lbs a month with my 29 gallon.


You have a massive CO2 leak.


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