the affect of bacteria on water??

Question

i know that there is a obvious answer to this question, but i need a better, more scientific explanation on why bacteria do not affect the pH of water like they would to say milk (bacteria break down milk particles which makes the pH more acidic).

Answer 1

Bacteria reduce the pH of milk because they use the sugar in milk(lactose) for energy and give lactic acid as a waste product. Since acids have a pH below 7, they lower the pH of milk. Water has no sugar for the bacteria to use, so they can't produce acid.

Answer 2

I would venture that they would have the improper nutrients in the water to digest.