When to fill Co2 Tank

[javatime]

I'm on my first 5# C02 tank fill and have about 250 psi showing on my regulator. Should I get it filled now or can I get another 1/2 keg on what is remaining in the tank?
I usually have it set at about 11-13#.

[psychodad]

Does your gauge not have the red zome marked refill? IMHO, that is the easiest way to tell. When you get to the end of the tank, the pressure is going to fall very rapidly, this red zone seems to work well enough for me to know that I can expect to get a new bottle when the keg is done.

[KillianBoy]

javatime,
I assume your CO2 tank is still inside, most members who have high pressure gauges with tanks inside have reported that their running from 500 to 250 PSI, most guys with or without high pressure gauges will count their kegs down, a 5 lb. tank will go as far as 8 kegs, if it's an important event then just go and get it filled just to be sure, it's only a few bucks lost if your at 2-3 lbs.
KB

[cubby_swans]

At what temperature is your co2 kept at? How many kegs of what size have you dispensed with your current CO2 tank?