Potassium permanganate (KMnO4
) is an oxidizing agent, which
is sometimes used as a pond treatment for oxygen depletion. It
is also sometimes used as a disinfectant or treatment for fish8
.
The addition of potassium permanganate at concentrations
above 4mg/litre has been reported to reduce the biological oxygen
demand of water in plastic pools17. The effect lasted for one to
two days post-treatment and was attributed to reduction in the
abundance of aerobic bacteria. However, treatment also reduced
daylight rates of oxygen gain by suppressing photosynthesis and
reducing algal abundance. This technique may in fact be
detrimental since it is only useful if potassium permanganate is
added in advance of oxygen depletion occurring17. However,
this technique might possibly be of some assistance as an
emergency measure if combined with additional supplementary
aeration to increase dissolved oxygen levels. This would be of
particular benefit at night when dissolved oxygen levels are at
their lowest.