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CO2 users

1626 Views 11 Replies 5 Participants Last post by  Mikaila31
been doing some reading on co2 injection and was trying to come up with a diy build without yeast but with a pressure tank needle valve and a diffuser. question is where is good place to buy affordable pressure tanks and would a empty propane tank work to hold the co2?
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Do you have a local gas area that provides the ability to refill CO2 in a canister? For instance in my neighborhood I have a local store called Airgas. They refill CO2 canister as well as sell them for a fairly decent price.
The AirGas near me is having a sale till the end of the month for a 5lb tank plus the first fill is like $82 then I'm not sure how much to exchange it but it's under $20 I know that.. and on average if you use a regulator with a silenoid (on off switch) that tank could last like a year with not using CO2 at night when the plants don't need it. I'm saving up and can hopefully get a sale price before Feb 28th cause I can't seem to find any used CO2 tanks that still have their hydro tests. Some places won't exchange or refill without it.
I used to use CO2 in a business. I had my tanks refilled at a fire extinguisher company. It was called Stop Fire. The tanks are a little pricey but, after the initial investment, refills are reasonable and should last a long time.
thanks for the info guys! just curious about a tank im trying to save in buying a tank since i have a few emtpy propane tanks alying around, i also have several co2 bottles for paintballs guns will any of these work in place of a "special" co2 tank?
They'd probably work but, you might have trouble finding someone to fill them. Apparently, there are all kinds of regulations. The typical CO2 tank is built like a "tank".
picked up a regulator and needle valve and a soleioid at lowes and if i can use a old propane tank then im all set, gunna call around and see if i can get it filled now. im sure a propane tank is just as sturdy as a co2 tank seeing how well its a propane tank that keeps pressurised flammable gas lol but well see. im sure theres some law or regualtion but ill let you guys know!
Sure hope it works out for you. You're right, seems strange that you can store propane in a certain tank, but not CO2.
Highly highly doubt you will find a place to fill a propane tank with CO2. Most tanks are gas specific, same goes with regulators. I would be surprised if a CO2 regulator would fit a propane tank without some DIY modification to the regulator stem. Each different type of pressurized substance usually follows different guidelines (CGA numbers) to make it so a CO2 regulator fits only CO2 tanks. That way it avoids mistakes as regulators are gas specific and will not properly regulate gases they were not designed for.

edit: A standard CO2 regulator will fit a CGA-320 valve and that is all. Anything else would require replacement/ modification of the regulator stem. Propane tanks use a CGA-510 valve.
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Highly highly doubt you will find a place to fill a propane tank with CO2. Most tanks are gas specific, same goes with regulators. I would be surprised if a CO2 regulator would fit a propane tank without some DIY modification to the regulator stem. Each different type of pressurized substance usually follows different guidelines (CGA numbers) to make it so a CO2 regulator fits only CO2 tanks. That way it avoids mistakes as regulators are gas specific and will not properly regulate gases they were not designed for.

edit: A standard CO2 regulator will fit a CGA-320 valve and that is all. Anything else would require replacement/ modification of the regulator stem. Propane tanks use a CGA-510 valve.
That's what I was thinking but, wasn't sure. Very helpful post. Thank you..
Highly highly doubt you will find a place to fill a propane tank with CO2. Most tanks are gas specific, same goes with regulators. I would be surprised if a CO2 regulator would fit a propane tank without some DIY modification to the regulator stem. Each different type of pressurized substance usually follows different guidelines (CGA numbers) to make it so a CO2 regulator fits only CO2 tanks. That way it avoids mistakes as regulators are gas specific and will not properly regulate gases they were not designed for.

edit: A standard CO2 regulator will fit a CGA-320 valve and that is all. Anything else would require replacement/ modification of the regulator stem. Propane tanks use a CGA-510 valve.
thanks a ton, i already bought a regulator from a big box sotre thinkign they were a one size fits all, which now its probobly the wrong one knowing what i know now. does the same go for the needle valves? once i get closer to getting a tank im going to pick your brain, sorry in advance lol!
it should say on the reg what it is compatible with. The main reason regs and tanks are different is the various compressions/properties of the gases. Regulators are very tough things and designed to hold up for a long time. The metals and seals in each type of reg are specific to give the greatest resistance to the gas it is designed to use. As far as needle valves i would think those are a bit more forgiving, but main issue I would see is how fine of accuracy they have as you do need pretty fine accuracy. Also threads/ports/barbs on the needle valve depending how you want to hook it up and what size tubing. Needle valve for aquariums are typically not that expensive unless you are aiming for something thats top quality.

For a CO2 tank, I would highly recommend just browsing Craigslist for a used tank. Thing is very very few places 'refill' a tank. What they call a refill is really just a swap and whatever tank you give them you won't likely see ever again. Your ownership just transfers from tank to tank. All you pay is for the CO2, which for me is roughly $20 for a 5lb tank. So IMO don't bother trying to hunt down a nice CO2 tank to start with. They come in steel and aluminum, both work fine.
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