Questions about CO2 canisters

[dpatte]

I have two gas canisters kicking around that I have had for years, and I believe they are CO2 canisters.

One has a valve with meter and an output that an airhose could slip onto. Is that called a regulator, and is that all I need at the canister side to pump CO2 into the aquarium? What do people recommend at the tank side for CO2 mixing?

Can I switch the regulator (or whatever it is called) to the other gas canister when the first canister goes empty?

How can I tell if the canisters contain CO2, and not something like propane, or nitrous oxide LOL

How long does a conisiter last before it has to be refilled, how much does it cost to refill, and where can I get them refilled?

For you tech CO2 afficianados, how many bubbles/min of CO2 are you adding per 100g?

[pm]

I wouldn't risk it unless I was sure it was co2.  There are many different gas cylinders out there.  A picture might be helpful in identifying the gas and components.

CO2 tanks need to be re-certified every 5 years I believe. They can't be refilled without re-certificaiton at that point.

[exv152]

Can you post pictures of the regulator and tank? A barbed fitting on the regulator, which is what it sounds like you have, isn't fine enough to control co2 output for an aquarium. You need a needle valve and bubble counter to fine tune the co2 coming out to about a bubble per second to begin. Then on the other end you can use a diffuser (in the aquarium). If you bring it to Pyromateck http://www.pyromateck.ca/ in Gatineau they can tell if it's co2, and the cylinder does need to be hydrotest every five years. The cylinder will last depending on its size and how much co2 you use.

[charlie]

Dave if you come to the season launch on Sept 22 nd you should have a full hands on know of CO2.
Hope to see you there