Introduction to Pond Fish
Setting up the pond
Building a pond
Thorough planning is the key to a successful result when building a pond, whether using a preformed pond unit or flexible liner. Think through all aspects of the project before you start; draw up detailed plans of the design and planting, and consider practical matters, such as which materials and tools will be required, and even how to dispose of the large volumes of excavated earth that will be generated.
Excavation of a pond site can be physically demanding. Although small ponds can be excavated manually, it may be worthwhile to rent a small excavator for more extensive works. Alternatively, some pond suppliers may build the pond for you. Soil conditions can have a considerable effect on the ease of construction. In sandy areas, for example, the soil is loose and easy to dig, but it can be difficult to cut clean boundaries; clay soils, by contrast, are easily shaped but present much more strenuous digging conditions.
Flexible liners are an extremely versatile material for pond construction and are ideal for informal ponds and unusual shapes. Detailed planning of the exact dimensions of the pond to be built is crucial, to avoid costly miscalculations of the amount of liner and underlay required.
- Mark the outer edge: Use soft sand to define the outer edge of the pond, and use this as a guide to where to start digging.
- Dig the first level: Start by digging down around the perimeter to what will ultimately become the level of the marginal shelf, before going deeper.
- Reinforce the outer edge: Make sure the site is level. Define the edge of the pond with one layer of bricks set in mortar, to reduce the risk that the edges will collapse.
PREFORMED POND UNITS
Creating a pond using a preformed unit is relatively straightforward. For a successful and lasting result, however, make sure the site is well prepared and free from stones or debris and that the unit is level when installed.
- Mark out the perimeter: Balance the unit on blocks and place stakes at regular intervals around it. Use string laid around the stakes to outline the area to be excavated.
- Excavate the pond area: Shape the hole to match the pond unit as closely as possible, including the marginal shelves. Rake and firm the base then seat the unit on a layer of sand so that it fits exactly and is completely level.
- Stabilize the unit: Slowly fill the pond with water, pausing at intervals to check that the unit is still level. Backfill around the edges with sand until the unit is secure.
- Lay the liner: Flexible pond liner should be laid over a suitable underlay material (above). Position the liner so that the overlap around the perimeter is even.
- Partially fill the pond: As you add the water, creases in the liner are evened out. Hold the edges of the liner or secure them with bricks.
- Lay the hard edging: An informal surround can be created using stone slabs laid in mortar. Be careful not to drop mortar into the pond, however, because it is toxic to fish.