To be continued...
If all the beer PSI gauges are reading abnormally low, you'll most likely need to switch to a new tank. Head outside!
There are two tanks hooked up. The direction that the handle is pointing is the tank that is currently opened up to the lines. You'll just turn the handle to the opposite tank and you're done. Allow a couple pours for the pressure to equal out.
Both tanks empty? You're going to need a crescent wrench. First close the valve on the top of the tank. Now using your crescent wrench loosen the male end of the hose from the tank. (Righty tighty; lefty loosie)
Swap the tank for a freshy, hand tighten the male end into the tank. Then tighten with your crescent wrench. Open the valve on the tank and make sure the blue handle is pointed towards the now full tank. Ta-da!
CO2 is its own self-sustaining beast. Though in the event of a freak occurrence there is a backup CO2 tank next to the large tank. Look for its blue handle to switch the lines over to it. Call Holston to get the CO2 tank refilled.