Every place where my family has lived has been fitted with a fish pond in the garden. These were usually dug by myself or the children and gave enormous pleasure to us all. Most important they provide atmosphere and water for the wild life. Some of the ponds we had were stocked with fish as well as tadpoles and frogs. Lying in bed at night listening to the frog calls was relaxing.
During the days, especially over summer, the water is essential for insects as well as birds, which are visit frequently. It is far more important to provide drinks than food as they will always find their own nutrition source and should not be dependent on humans.
Bees, butterflies, moths, and other insects all benefit from a pond. Keeping them stocked with fish is essential to keep down the mosquito population. A pump adds to the interest and keeps it oxygenated.
There are also beautiful water plants that can be grown in and around the feature. Some can be in pots or planted directly into the bank if it is a natural spring. Most ponds, however, are lines with either plastic, rubber, or clay and planting into those materials is not a good idea.
My ponds are usually built up into mounds on the sides making them appear deeper than they are. Beautiful Water Irises flower over summer and make a great show. Hebe and other flowering shrubs bring in the bees and wasps and they all drink from the facility.
Another great benefit to the garden is the humidity a pond offers. This allows special plants like ferns and such to be housed around the edges and even moss can be encouraged to decorate rocks strategically placed.
For me no garden is complete unless there is at least one water feature in it. At one stage my gardens had some six ponds scattered around. The bottom line is they are such a great asset that enhance the appearance of gardens that it is a shame not to include them.