Pond Stratification is a major problem in ponds and lakes and no pond is immune to it. Stratification happens when you have hot temperatures near the surface of the water and cooler temperatures down below. In and of itself stratification in a pond is not harmful. The real danger is “turn over”, which is what happens when the hot water on the surface gets pushed down into the bottom of the pond by perhaps a heavy rain storm on a summer afternoon. When the warm and cool water mix together it creates sort of a chemical reaction, rapidly depleting all of the oxygen in the water which more often then not leads to a fish kill.
Stratification is more likely to happen in ponds that 8 feet or deeper and it is most likely to happen during the summer months or it can even happen in late spring if the weather is hot enough. The best way to prevent this stratification and furthermore prevent fish kill is preventative maintenance in your pond or lake.
If you install a pond aeration system from Living Water Aeration, which is the company we recommend, then you typically never have to worry about stratification unless you undersize your system. There is no such thing as over aeration but there is such a thing as under aerating. When we recommend pond aerators in our customers ponds it is because this is the only cost effective way of destratification.
Destratification is what takes place when the temperature in the pond is uniform. Instead of having multiple layers of cold and hot water, the aeration system will mix the water giving you the same temperature above as below. Also, because the pond is now constantly turning over you do not have to worry about the a “turnover” related fish kill.