There is a hundreds of threads on your questions! I just kegged my first one. I think it depends on what kind of beer your kegging, equipment,fridge,keezer, temp, line length,etc. I've read a lot and just went with what I thought was right. I filled my keg with 5 gal of pumpkin spice porter,hooked new reg. and put in fridge at 40 deg. Put co2 at 45 psi and purged. New co2 tank said 700. Checked 12 hr later, keg said 36psi and tank is 475. I think drop in pressure is from getting cold. Checked 12 hr later after that, everything same. Did a sample, tasted great, still not carbed yet, a little flat. I think it will be ready in a day or two. I've learned alot here, but your going to have to experiment for yourself. Good luck!