Build Your Own Pond
Construct a pond with a flexible liner
A pool liner allows maximum freedom in choice of shape and size of a pond and is ideal where a natural look is required.
Cost effective and long lasting, there are a series of options depending on your budget. These range from inexpensive polythene up to quality products such as butyl rubber, which carry lifetime guarantees against sunlight degradation and other forms of wear.
Design your pond with large open curves and flowing lines. Avoid narrow gullies as they will not benefit from water circulation. Installing a pond liner
1. Use the outline of the pond marked earlier as a guide to remove any turf and all of the soil down to the first shelf level at a depth of around 23cm (9"). Level the sides sloping inwards at an angle of 200 from vertical to prevent the soil from caving in and in winter, when the pond freezes, avoid this causing damage to the liner.
Calculating the size of liner.
It can be very easy to underestimate the size of the liner you require and it's worthwhile outlining the shape of your pond using string, wooden pegs or a hose-pipe to enable accurate measurements to be taken. Irrespective of the pond’s shape or configuration calculating liner size follows a simple formula:
First determine the maximum length, width and depth of the pond. Then add double the depth to both the length and width measurements. This will allow for the slope of the sides and shelves and the overlap needed at the edge of the pond.
Our pond, for example, measures 2.5m x 3m and 60cm deep and requires a liner 3.7m x 4.2m which translates into the nearest sheet size as 4m x 4.5m.
Note: It's well worth buying the best quality liner. Look for those with at least a 20 year guarantee.
2. Use a plank and spirit level to make sure the hole is level. Check for any stones or tree roots that could puncture the liner.
3. Mark out the position of your inner deeper section using string or wooden pegs as before and dig out the inner section making sure the bottom is level.
4. Spread a layer of damp sand approx. 5cm (2") thick over the bottom and the ledges and then cover with liner underlay.
5. Position liner evenly over the hole letting it warm in the sun briefly to make it more flexible and easy to handle and make sure the centre touches the base of the excavation.
6. Place bricks or other weights around the overlap and begin to slowly fill the pond with water. The liner will stretch and mould itself to the shape of the pond and adjust the weights if necessary as the liner settles.
Be careful when filling the pond with water, if the liner is allowed to contort and stretch too much it may puncture.
7. When the pond is full, trim off any excess liner leaving an overlap of at least 15cm (6"). This surplus can be hidden beneath rocks, turf or paving slabs bedded mortar. Paving slabs should protrude slightly to hide the liner from view.
Don't forget to leave a convenient slot between the slabs for the pump cable.
Adding filtration
The powerful combination of the Max-Flo 6000 pump and the Pressure-Flo 8000 filter is a great start to the care of your new pond. The sizes chosen are ideal for larger, fish-stocked ponds up to 4500 litres (1000 galls).
Pressure-Flo is an extremely hard working filter which will make pond care so much easier, tackling the problems of cloudy water and preventing the harmful build-up of toxins. As well as providing mechanical and biological filtration, Pressure-Flo also contains a UV lamp to deal with the problems of unsightly green water, leaving the pond crystal clear.
The Max-Flo 6000 pump is immersed in the pond and feeds water to the filter which, in turn, feeds clean water back to the pond. Alternatively, because the filter is pressurised, water can be fed up to the head of a waterfall which can be constructed with excess pool liner and excavated soil.
Make sure all the electricalcomponents are installed correctly, if inany doubt get a professional electrician to install them. Any electricity and water combination can be lethal. Before you cover up the wiring with stones, turf and piping, take a photo, it may help in the future.
Constructing a pre-formed pond
Pre-formed ponds made from polyethylene or glass fibre reinforced plastic are available in a range of sizes and both formal and informal shapes. They are particularly durable and quite easy to install provided that youchoose a design without too many irregular corners. Project: Construct a pond with a rigid, pre-formed liner Although pre-formed designs are an ideal solution for a small pond it is wise to consider their limitations.
Even the largest models offer less than 10 sq. metres water surface and the depth is usually a maximum of 60 cm (2') or so. Large water lilies require more space and a greater planting depth than is normally offered and the very shallow depth designs are not really suitable for over-wintering fish. But for an easy way of creating a small pond that will remain perfectly waterproof and last for years you could not make a better choice.
Raised ponds
Raised ponds add height and interest to flat areas in the garden, terrace or patio and pre-formed liners are absolutely ideal for this use. Use formal, square shapes as raised ponds don't really lend themselves to 'curvy' schemes. You can use a variety of different materials to finish off the pond - tiles, old railway sleepers, bricks, stone, paving slabs - use your imagination or take a cue from the existing style of your garden. A raised pond can also be part of a larger pond project, acting like a 'header' tank, feeding a cascade of water into the bigger pond. There are various self-assembly kits available if you want a really easy-to-construct raised pond project.
Installing a pre-formed pond
1. Place the pond in position and carefully mark out its shape with pegs or a trail of sand or flour. Don't turn the pond upside down to mark out the shape, as this gives a mirror imageof the pond.
2. Check the surface level and start digging down to the shelf.
3. Reposition the pond, mark out the inner deeper section and continue digging out to the bottom. Remove any loose stones or sharp objects from the hole and spread a layer of damp sand, approx. 5cm (2') thick, over the bottom of the hole. Check the level at the bottom.
4. Position the pond in the hole and firmly backfill with sand or soil. Fill with water and leave to settle for at least a week before finishing off with your choice of edging. Pre-formed ponds must have good all round support. Make sure you pack in the sand between the hole and the sides of the pond.
Installing a fountain pump and filter
Laguna pond pumps are easy to install and quite unobtrusive in use, out of sight under water in the pond. The power cable is all that shows above water and this can be buried below ground level, protected with a suitable grade of conduit. This will avoid any accidents occurring when later working in the garden.
The Laguna Powerflo Max submersible filter, combined with a Laguna Powerjet 800 pond pump, provides an excellent form of filtration for this size of pond. The handy Powerflo Max not only ensures high performance biological filtration but also protects the pump from clogging thanks to its generous sized mechanical filter compartment.
Maintenance is also quick and easy, because the filter can be conveniently located on one of the shallow shelves on the pond edge and is easily accessed by disconnecting from the pump using the 'click-fit' coupling.
- People will always spend more time sitting by water so plan your raised pond with this in mind. You will need to build sturdy, low walls to enclose the liner and cap the top edges with tiles or wood.
- Really small features can be very simple, just water and a few plants - you don't really need a pump or an electricity supply - but it won't be big enough to support fish.
- A raised pond is an ideal way for disabled gardeners to get closer to their pond, fish and pond plants.
- High-sided ponds are a bit more child-friendly than sunken ones, at least until the child is old enough to climb!
- Maintenance is much the same for a raised pond as any other but in winter tiny ponds may freeze solid. It's a good idea, in this instance, to drain off the water and use the space to overwinter potted plants.
Try linking two small ponds together, at different heights. This way you can create a mini waterfall or spouting feature to animate the display.