Why “angry” water?

Because it is not still? Not sure. It is a name someone used many years ago and it stuck.

Standard

I usually fill the keg with 18 liters of warm tap water. The water is filtered before it goes into the hot water cylinder (geyser), so most of the nasties are taken out. The water still contains some chlorine, but not at such a level that it is noticeable. The keg is placed in the kegerator and linked up to the CO2 at 30 psi and left for a week to carbonate.