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 Pond Aeration Specialists


Thermal Stratification of Ponds

One of the principal reasons for pond aeration systems is due to the thermal stratification that can take place.  This occurs as the warmer water rises toward the surface forming a warm water layer with the cold water at the bottom.

Thermal stratification becomes particularly troublesome in the summer months for ponds that are 8 to 10 feet or greater, as the warmer water rises to the surface and the denser cold water sinks toward the bottom of the pond.  The difference in density due to the temperature creates these thermal layers that inhibit any mixing between the layers.  Thus the lower cold layer of stagnant water, unable to bring in dissolved oxygen through the wind or diffusion, becomes less and less oxygenated. 



Thermal stratification causes a depletion of oxygen and algae growth.

Benthic layer

3 degrees or more between top and benthic