Its not the tank but the regulator on the tank that is usually being refereed to. The pressure is the output pressure, the pressure that the air is at when it comes out of the tank. Air is stored at either 3000 or 4500psi but putting that straight into your gun would blow it apart. So the regulator controls the pressure that air can be released into the gun. A high pressure tank puts I believe, about 800psi into your gun while a low pressure runs around 450. The differences depends on the needs of your gun. Typically you should run a tank at around 200psi more than the operating pressure of your gun. This will ensure ample air flow into the regulator and eliminate most issues of drop off and the like. My cyborg RX runs at 180-200psi operating pressure so my tank runs at around 450, classified as low pressure. Some guns run much higher and need a high pressure tank. In general, all you need it that 200psi leeway and anything over just puts extra stress on the regulators in your gun. If you slap an hp tank on my rx it will still run but the HPR on my gun will need to control much more air than it should need to. Hope this helps and is not too confusing.
reg tester, the cheap way, an old on/off ASA with a 0-800psi gauge installed instead of a macroline fitting...
__________________ Originally Posted By Paper Cut: " To OP: you are aware that most people who picked the Geo are only picking it since it is made by Eclipse but have no idea that the Geo is actually a Dangerous Power G4"
With a minute amount of research you should be able to uncover the reg output assuming it has not been tampered. Yes a reg tester is the most straight forward but I would go for a bit higher pressure gauge, usually a 1200psi for tanks. Each brand has their own way to tell what pressure the reg is at, some will say on the reg, some are color coded, others have different color spring kits. Do you have a specific reg in mind? A picture of said reg would make this much easier.