Formal ponds are frequently seen in the grounds of European
stately homes, reflecting a gardening trend that began in North Africa. Such ponds generally have
few plants present, other than water lilies.
invariably kept in a larger formal design of pond. Such ponds
are costly to construct, however, not just because they need
to be large, but also because they require an effective filtration
system to maintain water quality and clarity.
Naturalistic ponds are simple and inexpensive to create
using flexible pond liner . At certain times of year,
however, the fish may not be particularly conspicuous in this
type of pond; during early summer, for example, the water
may be green with algae and the pond partially covered with profuse plant growth. A filtration system is less essential in a pond of this type, but regular maintenance is required to remove dead plant material and clean out silt
Depth is an important consideration, especially in temperate areas. Fish instinctively retreat to the bottom of a koi pond as the temperature drops toward freezing. Ponds should, therefore, include an area that is at least 4 ft (1.2 m) deep, to ensure that it will not freeze to the bottom in even the most severe winters
The availability of modern pond construction materials provides a wide choice for the hobbyist. Creating a pond using flexible pond liner or installing a preformed pond unit does not require advanced construction skills and can be relatively inexpensive. Large concrete ponds, by contrast, are considerably more expensive, and may even require the services of a professional installer.
A wide range of flexible liners and preformed pond units mare available to suit most budgets, but it can be a false
economy to purchase the cheapest option. Less expensive liners, such as polyethene, may not last as long as higherquality flexible liners, such as PVC and butyl rubber, which are more resistant to attack by the ultraviolet component of sunlight. Butyl rubber is probably the best material to choose, partly because it is very elastic and so will not crease as much during installation as other materials. A PVC pond liner is a somewhat cheaper option, with a correspondingly shorter life-span; if choosing PVC, select a thicker grade, typically 1 mm, with a reinforcing nylon weave providing extra strength and durability. Preformed pond units are also available in a range of materials, of which rubberized versions are generally the most durable. Flexible pond liner is sold by the square foot, in rolls
of various widths, so careful planning is required to be sure you purchase sheeting of the correct dimensions.The amount of liner required is easily determined for any shape of pond using the following method. First, determine the length of the pond at its longest point and the width at its widest point. Next, adjust these dimensions to allow for sufficient liner to fit into the deepest part of the pond: to do this, multiply the maximum depth of the pond by two, and add this to both the length and width figures respectively. Finally, add a further 18 in (45 cm) to each dimension to provide extra liner to overlap the edge of the pond; the final figures give you the overall width and length of liner required.
- Ponds should only be
constructed in areas where
the ground is relatively level
- Choose a location that
allows you to view the pond
from inside the house.
- Consider the availability of
a power supply for running
filters and fountains.
- Avoid building a pond
close to trees, because the
growth of their roots may
damage the foundations or
puncture the pond liner
- Avoid areas that are
naturally prone to becoming
waterlogged, because excess
water can collect under the
- Site the pond in a
sheltered spot, to stop leaves
from blowing into it.
- Choose a site that is not
in direct sunlight during the
hottest part of the day.