LANDSCAPE SERVICES
THERMAL
STRATIFICATION
Pond and lake water management is
no easy feat, with plenty of hazards
to water health and quality.
Thermal stratification is one such
example, where water separates
into distinct thermal layers, with
cold water sinking to the bottom
and warmer water rising to the top.
Without strong winds or running
water to help move the water, the
thermal layers don’t mix. As such,
the lower level of your lake will
suffer with massively reduced
dissolved oxygen levels.
If left alone the water quality of
larger bodies of water can decrease
hugely if affected by thermal
stratification. The most extreme
cases take place in the summer,
however it’s an issue that can occur
throughout the year depending on
the geographical location and depth
of your lake.
When the natural process of
anaerobic digestion occurs, whereby
bacteria break down organic and
biological waste into carbon dioxide,
ammonia and methane, this further
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reduces the amount of dissolved
oxygen in the water. This can be
incredibly damaging to any aquatic
or plant life and result in stagnant
water.
However, with Otterbine aerators
you can prevent thermal
stratification from happening or
solve the issue if it already has,
by ensuring you maintain healthy
levels of dissolved oxygen.
It’s important to remember that
you can’t over-aerate water. In
fact, water’s capacity to hold
dissolved oxygen reduces as the
temperature rises; at the same time,
the metabolic rate of nature’s clean-
up organisms (aerobic bacteria)
speeds up significantly, resulting in
increased consumption of dissolved
oxygen at a time when less is
available. Ensuring you always have
enough oxygen isn’t the easiest task
when dealing with the change in
seasons. A rise from 14 degrees to
27 can see oxygen capacity reduce
by 40 percent, so making sure
your aerator is always meeting the
saturation point is highly important.
It’s recommended to aim for around
80 percent over the saturation point,
to allow for changes in temperature
and other external factors.
With the proven high oxygen
transfer rates of Otterbine’s
comprehensive range of aerating
fountains, you can easily increase
the dissolved oxygen levels in
your lake or pond, preventing or
curing stagnant water, algae build
up and bad smells for clean, clear,
healthy water. And with Otterbine’s
decorative range you can make your
lake or pond an appealing beauty
spot at the same time.
www.otterbine.com
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