co2

Sorry, couldn't find this using the search feature. Anyone seen a link to that chart that shows how much CO2 is left in my tank at a given temperature? I'd like to know how long till my tank is out, based off the reading on my regulator.

The only way that I know this to be done is to weight the tank when full and then subtract the tare. Should be marked on the outside of the tank.

EDIT:
I'll add that the pressure (at a given temperature) will remain the same until all of the liquid CO2 condenses into gas. It is at that point that your gauge will start to show a rapidly decrease in pressure. That's why it's not very effective for what you are looking for.

Yeah I've heard that method. I just thought I remember seeing a chart somewhere based on pressure. If the only way really is by weight then what did I pay the extra couple bucks for the dual gauge regulator for?

See above.

cool thanks for the info....so for my next keg setup I go with the single gauge then.

Well it does give you some indication when it's time for a fill.
That's worth a few buck in my book.

The second guage shows the outout presure. If you get a single guage regulator then you will have only the tank presure guage and no way to know exactly what the output presure is.

It lets you know if you've had a leek. It shows 0.

I've used regulators for several purposes, and I ALWAYS get them with dual gauges. Call it 'piece of mind'.