[galapagos jim]

How long should I expect a canister of O2 to last? I seem to be changing out every 2nd or 3rd brew, and it's getting expensive.

I'm aerating with pure O2 for about 90-120 seconds, with canisters from the hardware store that are like this:
http://www.amazon.com/WORTHINGTON-CYLINDERS-333666-Disposable-Cylinder/dp/B0086AKIBW/

Hooked up to a regulator and .5 micron stone from my LHBS.

Possible that I've got a slow leak in the regulator head? Should I disconnect it while not in use?

[tygo]

A canister like that lasts me maybe 10 batches, maybe more.  I've never actually kept track I just know that it lasts for a long time, and that includes giving a shot to my starters as well.  I always disconnect the regulator when I'm not using it. 

[Slowbrew]

I'm done 5 batches with my first can so far.  I was taught by Dad and Grandpa to always remove the regulator from any gas canister when not in use.

Paul

[ajk]

Funny, for me, the red disposable bottles seem to last longer if I leave the regulator on.

[majorvices]

I made the mistake at first of dumping the o2 in too fast and blowing through canisters. Be sure you are just trickling it through. If you dump it in too fast you are wasting it anyway as most o2 will just pour out of the surface and not diffuse into the wort.

[redbeerman]

I made the mistake at first of dumping the o2 in too fast and blowing through canisters. Be sure you are just trickling it through. If you dump it in too fast you are wasting it anyway as most o2 will just pour out of the surface and not diffuse into the wort.

+1

[dak0415]

I get about 20 batches out of mine, I'm on my 3rd bottle.  They seem to last forever.  Only open the regulator enough so the bubbles just make it to the top of the wort, 2 minutes worth.  30 seconds for a big (4L) starter.  I remove the regulator when not in use.

[ultravista]

I have a red O2 bottle from Home Depot and push it through a 2 micron stone. The bottle "felt" empty when I bought it and it feels the same today after 5 or 6 batches. I always trickle the flow and keep the regulator off when not in use.

There is no way to gauge the volume left. Maybe a spare bottle would be handy.

[Joe Sr.]

I always remove the regulator from my O2 bottles.  If it's empty after two or three batches you either have a leak or you are using WAY too much O2.

I put the stone by the side of the carboy so I can see the O2 coming out and adjust the flow so that there is just a trickle.  I don't know how many batches my last bottle lasted, but at least 10.  It was also an extra large bottle, but not that much larger.

[galapagos jim]

Thanks for the replies, all. I had been cranking the regulator all the way open, so it looks like no surprise that I was running through them so fast. The instructions that came with the kit from the LHBS weren't very detailed. They did tell me to keep a spare bottle on hand, so I've never been short of O2.

And I'll take the regulator off when not in use. I suspect that doesn't have so much to do with it, but fewer parts that can fail = lower probability of failure.

[davidgzach]

I have a mix-stir on hand in case my O2 runs out or I need a good whirlpool. Used it before going O2 and it works just fine.....

Dave

[majorvices]

Thanks for the replies, all. I had been cranking the regulator all the way open, so it looks like no surprise that I was running through them so fast. The instructions that came with the kit from the LHBS weren't very detailed. They did tell me to keep a spare bottle on hand, so I've never been short of O2.

And I'll take the regulator off when not in use. I suspect that doesn't have so much to do with it, but fewer parts that can fail = lower probability of failure.

I use my hearing as well as sight to get a feel for the flow. Put yer ear up to the regulator while you feather the flow in on the dial.

[mabrungard]

20 Batches is about right.  If you are getting less than that, you are doing it wrong.  Oxygenate, long and slow.  If you see more than a hint of bubbles at the wort surface, the flow rate is too high.  "Blasting it" is another way of saying "wasting it".

[tygo]

20 Batches is about right.  If you are getting less than that, you are doing it wrong.  Oxygenate, long and slow.  If you see more than a hint of bubbles at the wort surface, the flow rate is too high.  "Blasting it" is another way of saying "wasting it".

Martin - How long do you usually oxygenate at that flow rate. 

I'm likely wasting too much the way I'm doing it.