How long does a O2 bottle last?

[keggermeister]

Thinking of setting up an o2 injection system at my brewery.
I am debating getting a 5-10lb o2 bottle contract for it, My question is for those of you who use the small (1lb?) bottles available in stores.
How long doges one of the small bottles last?
How many 10 gallon batches would i be able to oxygenate with a small bottle??

[DannyW]

Like Chris White says, "it depends."

I think on the side of the bottle it says 12 minutes. I suppose that is at full flow rate. I do 60sec per 5 gallons on brew day, then a little squirt here and there for starters or if a ferment is slow to take off. Six 10-gal batches seems about right, I guess. I've been using the current bottle long enough that I have forgotten how many.

I did learn early on to remove the regulator from the top of the bottle when I'm not using it. I guess mine has a little leak somewhere because the bottle will drain itself in a couple of days just sitting on the shelf if I leave the regulator attached. With the reg off, it will sit for months without losing any.