I only put about 1 ounce of bleach into my fresh water hose, and that is plenty to bring up the free chlorine levels to the 15 PPM level. That is plenty to kill the bacteria.
Any more and you get a lot of odor, and it will stay around through a couple of filling the fresh water tank and dumping it!
For a swimming pool, 1.2 PPM is plenty to kill that bacteria. City water systems try to run 1.0 PPM as the water leaves the plant. Once it hits the rusty city pipes, then it tends to drop a little, as it is killing any bacteria in the lines. . .
Fred.