I think most folks let their fresh water "run clear". It doesn't have to run long to clear up.
I do the bleach treatment as a pre-season item. ... hook up the city connection and check for leaks, disconnect city connection and start water into tank, turn pump on and check for leaks, if OK, add bleach solution and finish filling tank
Later, after flushing system I figure I'm ready to go - at least as far as fresh water is concerned. And there's is no anti-freeze left at that point.