Obviously, this population (typically doubling in size every 15 minutes)
cannot increase forever. At some point, the food source will be
depleted, or some other change in the environment will cause the
population to level off or decrease. These changes could be pH,
temperature or oxygen content of the environment. The introduction
of poisons to the environment (bleach or disinfectants) may have
negative effects on the population, as well as competition from
other types of bacteria.