Types of Containers for Garden Ponds
The cheapest form of container uses a plastic liner to contain the water in an excavation. This liner is made of polythene, which breaks down when exposed to sunlight, so it must be shaded between the pool edge and the water level. It has an estimated life of just a year or two, and can only be recommended as a temporary structure. Other liners using plastic have a guaranteed life of three years for the plain and ten years for the laminated varieties; the best quality is the liner made from butyl rubber; this is guaranteed for 15 years but has a life expectancy of over 50 years, and should give a lifetime’s use without trouble. With a liner, a pond of almost any shape or size can be made, limited only by your purse and the size of your garden.
Concrete is a wet form of construction that is labour intensive and involves the use of shuttering to contain the concrete until it has cured. Concrete is fine where there is a good solid foundation underneath and the water table is not close to the surface, but where there is a chance of movement it can crack; this will allow the water to seep away, and if the crack is very fine it is difficult to trace for repair.
Pre-cast pools are made from plastic in various weights and in fibreglass. The cost varies and, as in most things, you get what you pay for. The cheapest models are thin and vulnerable to damage; the thicker plastic ones are either semi-rigid or rigid and strong, but more costly; and the most expensive are constructed from fibreglass, which should give a lifetime’s use. These pools are fine if the shape and size available happens to meet your requirements.
Should the worst occur and your pool start to leak, there are repair kits that will seal the pool, but usually you will have to empty the water out, store the livestock in a separate container, and replace and balance the water before the livestock can be replaced.
Water Features and Water Movers for the Garden Pond
For most gardeners achieving water movement entails some form of power to lift it to a higher level so that gravity draws it back to its original level. This usually takes the form of an electric pump that forces the water through a jet or series of jets to form a fine spray that falls back into the water splashing and extending the water’s surface to expose it to as much air as possible.
Alternatively, the water is lifted to a higher level so that it can run down through a stream over a waterfall or series of ledges where it can splash and increase the oxygen level. Once it has returned to the pump level it is then pumped up again to repeat the cycle.
Apart from the important oxygenating effect, the movement of water is pleasing to eye and ear, particularly on a hot sunny day when it has a cooling effect and will perhaps lay a little dust. There are more gentle forms of moving water that are decorative, where a tall fountain is unsuitable. In draughty areas where the spray drift might be a nuisance, a lower and more concentrated form of fountain can be obtained by using a bell-fountain, which gives a thin, dome-shaped curtain of water around the fountain head.
Another form of movement can be achieved by pumping the water through the central hole in a millstone so that it bubbles and spreads over the stone surface, then trickles down the sides to be returned to the pump.