# CO2 tubing



## geezer (Jun 7, 2006)

I got a Milwaukee Co2 regulator combo but still haven't got any tubing. I went and bought a co2 cylinder today and she said she had no tubing to fit over the top bit of the bubble counter. she unscrewed it and found some piping.

I don't like the idea of the piece of the top unscrewed. anyone know the exact type of tubing i need for the Milwaukee Co2 regulator? 

thanks for any help!:yawinkle:


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## trenac (Jul 16, 2004)

I use the blue air tubing, which hooks directly to the bubble counter.


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## Rex Grigg (Jan 22, 2004)

The blue airline tubing is silicone which leaks CO2 like no other tubing commonly available on the market. Standard air line tubing (vinyl) will work. I prefer to use polyurethane.


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## John N. (Dec 11, 2005)

I use the regular vinyl clear airline tubing, and also the tubing that comes with the Hagen. I still doubt for our purposes that we need special tubings. I've been running a 2lb cylinder with flexible silcone tubing for 4+ months at a good 3-4 bps, off at night. So I'm not overly concerned about wasted CO2 if I'm refilling a CO2 cylinder once every year or so.

But if you want the polyurethane tubing can be purchased from Mr.Grigg I believe, and also you can run over to Home Depot and find some of the tubing there. usplastics.com sells it too.

-John N.


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## invisibleshopper (Jul 6, 2006)

On the tubing selection guide that Rex links too, the chemical resistance summary is listed for each tubing.

Which one would CO2 be considered under:

Acids weak, Acids strong, bases weak, bases strong, ozone, uv light?

Along with the permeability number I'm sure you would want to consider the chemical resistance as well.

Thanks,

KLT


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## trenac (Jul 16, 2004)

Rex Grigg said:


> The blue airline tubing is silicone which leaks CO2 like no other tubing commonly available on the market.


I will have to disagree with Rex on this. I have been using the blue tubing for years with no leaks. It stays soft and does not get brittle like some of the white tubing does.


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## John N. (Dec 11, 2005)

invisibleshopper said:


> Which one would CO2 be considered under:
> 
> Acids weak, Acids strong, bases weak, bases strong, ozone, uv light?


Though, I'm not sure CO2 alone can be classified as an acid or base. It would be more of an weak acid when combined with Hydrogen ions, like from water H20.

CO2 will rapidly react to water to form carbonic acid (H2CO3), which will dissociates into hydrogen and bicarbonate ions (HCO3-)...weak acids.

In regards to tubing, I think the main issue with CO2 tubing is the permability and brittleness overtime. Replacing the tubing every year, or with every refill will probably be enough to address that problem for our purposes. Most of use aren't using 10 feet of tubing from Cylinder to reactor/diffuser. 3-4 feet isn't going to empty your cylinder very quickly with the pressure we use through our tubings. I use any tubing I have laying around, and worry not much about losing CO2.

-John N.


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## ringram (Jan 10, 2005)

I have black Co2 tubing (bought it off Glass gardens about a year ago *I think*) that has become quite hard and probably brittle too, although I haven't really checked. I'm going to be re-doing my setup a little bit in the next couple days as I'm adding a UV Sterilizer and will clean up the arrangement of the other components. I noticed that the Co2 tubing is quite hard and not all that malleable and its merely been a year (or a tad more). I would say that the best bet would be something more bendable that has the longest longevity. I'm slightly less concerned with miniscule amounts of Co2 leaking than I am about having to track down more Co2 tubing and reconnecting everything each year.


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## Overfloater (Apr 2, 2004)

trenac said:


> I will have to disagree with Rex on this. I have been using the blue tubing for years with no leaks. It stays soft and does not get brittle like some of the white tubing does.


I have the same experience.


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## Rex Grigg (Jan 22, 2004)

Not leaks. Diffusion. Silicone tubing can lose up to 6% of the CO2 per foot. Of course it's such a slow process you would never notice it.


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## Ajax (Apr 3, 2006)

The biggest problem with the tubing specifically made for CO2 is that it is not very flexible. It is almost impossible to shove that tubing onto the end of a diffuser. One way to decrease your loss a little is to use the clear airline tubing to run from your diffuser out of the tank, say to like the bottom, and then use the hard plastic airline splices to connect the clear tubing to the CO2 tubing which is connected to the bubble counter. This also looks much cleaner in the tank then having black, blue or grey tubing in there.


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## wiste (Feb 10, 2006)

> The biggest problem with the tubing specifically made for CO2 is that it is not very flexible.


To increase flexibility, soak tubing in hot water for a few seconds.
I am using the following tubing with a milwaukee CO2 regulator.
http://www.marinedepot.com/md_viewItem.asp?idproduct=CO1511


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## Left C (Jun 14, 2005)

I believe Rex posted this chart some time ago. Check out the silicone! http://www.coleparmer.com/techinfo/...E,C&htmlfile=SelectingTubing.htm&Title=Search


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## Left C (Jun 14, 2005)

wiste said:


> To increase flexibility, soak tubing in hot water for a few seconds.
> I am using the following tubing with a milwaukee CO2 regulator.
> http://www.marinedepot.com/md_viewItem.asp?idproduct=CO1511


I use this same tubing from Marine Depot plus the 1/8" ID Tygon lab grade on two tanks.

I use 3 feet of the Marine Depot "semi-rigid" CO2 tubing from the regulator to a brass check valve. From the brass check valve to the diffuser system I use the Tygon lab grade for flexibility.

I might try the Tygon FEP-lined down the road instead of the Lab grade because of the much smaller permeability specs.


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## geezer (Jun 7, 2006)

I'm just using clear airline tubing at the moment. Not sure what material that would be.

I got some of the black tubing with the reactor but it's not long enough, i could try half and half I suppose.

off out to home depot now to see if I can get any


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