Mag pressure??????

[(sic)kness]

If i was to run a 68 3k tank on a mag would i have to do anything??? Like adjust something, because i heard that it will just regulate the pressure from a preset tank (around 800-850 psi) to the right operating pressure. Is that correct?

[FooTemps]

Screw in the preset and play.
The tank puts out 800-850 psi and the valve regs it down to the right pressure.