Aim to mimic natural ponds and create a wide range of habitats. This will encourage high species diversity. It can be done by:
Provide some deeper water. Make sure that some part of the pond is at least 50cm deep to provide some unfrozen water even in the coldest weather.
Chose a lining material that has a long life span. Unless you have a high water table and a heavy clay soil, you will need to line your pond. A butyl liner is best and should last for 25 years.
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