I herd that bacteria cannot live in an alkaline environment
This is not true. Many pathogens, including most bacteria, thrive in an alkaline environment. That is why so many areas of our body are acidic such as the stomach and skin. The acids are part of the body's defense mechanism against pathogens. Need a good example? Look at Helicobacter pylori bacteria, which causes stomach ulcers and cancer. It can be killed by the acidic environment of the stomach so to protect itself the bacteria releases alkaline ammonia to neutralize the stomach acid.
I started by drinking alkaline water which is cheap