what tubing is co2 safe?
- Thread starter Linda S
- Start date
Silicone is probably the WORST you could use.. So much so, that you could almost use it as a diffuser! When I say silicone, I mean the really soft stuff.... the clear plastic that us most common is not actually silicone, but vinyl. Vinyl isn't great either, but a lot better than actual silicone... I hope this helps to stop people suggesting silicone.........
I am suggesting you read this entire paper,as it is the best thing I've read to date on DIY co2.But,here is the quote again:From:"A Treatise on DIY CO2 Systems for Freshwater-Planted Aquaria"
"Getting the gas to the tank water is the next consideration. Tubing should be selected based upon several factors. One is pressure retention, or the ability of tubing to retain its shape under pressure. As tubing is put under pressure, it should not expand in relation to its diameter. Also the tubing will need to be inert; meaning not break down over time due to chemical reaction with the CO2 gas internally or the air or water externally. This pretty much eliminates standard airline tubing used for fish tank aeration. Another consideration is flexibility.
A good candidate for this application is silicon tubing. It does not react with CO2 as quickly, has good pressure retention characteristics and is very flexible. There is also special tubing designed specifically for carrying CO2 gas, and I would encourage spending the few extra dollars needed to use this. But silicon tubing will last for several years, and is in keeping with the cost savings approach DIY implies"
I have used silicone tubing for years with no brittleness or loss of co2.Just experiment with what you will and come up with your own conclusion.That is what this forum is all about.
"Getting the gas to the tank water is the next consideration. Tubing should be selected based upon several factors. One is pressure retention, or the ability of tubing to retain its shape under pressure. As tubing is put under pressure, it should not expand in relation to its diameter. Also the tubing will need to be inert; meaning not break down over time due to chemical reaction with the CO2 gas internally or the air or water externally. This pretty much eliminates standard airline tubing used for fish tank aeration. Another consideration is flexibility.
A good candidate for this application is silicon tubing. It does not react with CO2 as quickly, has good pressure retention characteristics and is very flexible. There is also special tubing designed specifically for carrying CO2 gas, and I would encourage spending the few extra dollars needed to use this. But silicon tubing will last for several years, and is in keeping with the cost savings approach DIY implies"
I have used silicone tubing for years with no brittleness or loss of co2.Just experiment with what you will and come up with your own conclusion.That is what this forum is all about.
I guess I was hoping for too much. Also, silicon is a metal...... I think the word you are looking for is silicone....
(As per the link that squawkbert posted, vinyl has a CO2 permeability rating of 360, while silicone is 20,132. I'd say that makes it fairly permeable, yes?)
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have you tried switching to a more co2 proof tubing to test that? when i switched from silicone to co2 proof tube i saw a increase ppm co2 in my tank. i believe its like a 10% loss though i could be wrong.
you wouldnt necessarily notice any loss in co2 unless you switched tubing.
Well,the author of the article on DIY co2 misspelled silicone.But,thank you for the correction,Speak and Spell. 
Anyway,he says in the article that there is actual tubing for co2 and it is worth the extra money and I agree.However,that doesn't mean that silicone tubing will not work until one can get a hold of the good stuff...
Anyway,he says in the article that there is actual tubing for co2 and it is worth the extra money and I agree.However,that doesn't mean that silicone tubing will not work until one can get a hold of the good stuff...
the lower the number in the co2 column the better... anything with a dash will do as stated.
another notable post
congrats, and good choice. :dance2:
Bob's tubing is OK, cheap and easy enough to work with (PVC, I presume)
- but if you need a long run of tubing, go w/ untreated Tygon (the more pressure treatment you give this material to impart resistance to other chemicals, the more CO2 permeable it becomes), PFA or PEEK (though some adaptors may be required if you can't find 1/4" ID stuff and heat it adequately to make connections the old fashioned way).
- but if you need a long run of tubing, go w/ untreated Tygon (the more pressure treatment you give this material to impart resistance to other chemicals, the more CO2 permeable it becomes), PFA or PEEK (though some adaptors may be required if you can't find 1/4" ID stuff and heat it adequately to make connections the old fashioned way).
