There are two types of ponds, above ground and in-ground, which is right for your garden?

This is a 250 word (approx) summary of a chapter from my water gardens book pictured to the left.For a complete list of summaries see the right hand column

Concepts:

pond, water, metres, litres, fish, rectangle, squares, liner, installation, design, edging, plants, floating rocks, deep, hole.

Summary:

- This section is important to -- don't make a mistake here.

- Only you can choose but we can help you make a wise choice!

- Essentially there are two types of ponds: above ground and in-ground.

- The above-ground pond is by far the easiest if a pre-formed design is selected.

- For the item above that is 3 metres long at its widest point installation needs only 2 people to lift it and place it in position.

- On the other hand above-ground ponds can be difficult to build from scratch without good bricklaying skills.

- In-ground ponds, an example of which is shown below need a hole to be dug that then has to be lined using a flexible liner, a preformed design or a concrete/fiberglass shell installation.

- Since the pond is the starting point of the project.

- It should be sited correctly with the following points uppermost in your mind.

- The pond installation if it is to be dug into the ground is the most cumbersome and therefore the most difficult part of the total project so do your best to get this right.

- Seek help if you do not feel comfortable with doing the job yourself.

- Most important do not rush it - take your time, get it to fit well into the hole, create good back fill and edging support where necessary and get the pond level in its hole if it is a pre-formed unit.

- Pre-formed ponds are best for volumes less than 500 litres because they are ready to install and in the case of the glassfibre features come complete with surround built in so once the pond has been installed there is no further work required to give a finished effect.

- Remember an in-ground pond will always appear significantly smaller once installed than it looks out of the ground.

- To assist in this task and before you fill the pond to the top check that the water is level after filling with only a few centimetres of water -- then if not level it will be easy to remove the pond water and do a bit more excavating and levelling.

- You have the choice between PVC, Polyethylene, Butyl rubber or EPDM rubber.

- An important point with liner is to ensure that the exposed liner above the pond surface is protected from continuous direct sunlight by creating an edging that will shade the exposed liner surface.

- Use the method outlined below to decide what size liner you need to buy to fit your desired pond dimensions (all liner comes in square or rectangular form).

- First of all the width of the liner:

- You will often be told that a pond should be at least 1 metre or more deep.

- Unless you want a very large pond and you have a particular interest in wanting to grow large fish then a depth of between 35 cm and 60 cm is perfectly adequate for a basic garden pond.

- On the other hand there is nothing wrong with deeper ponds and there are some advantages such as less temperature fluctuation, greater protection from birds and so on.

- Black is an excellent colour for a pond since it creates contrast for the fish and plants and also gives an illusion of greater depth.

- Whatever type of pond you install ensure that you create a couple of shelves at different levels to accommodate later planting of aquatic plants.

- While on the subject of water lilies these plants do not like water that moves too much - they will not tolerate splashing for example and therefore should not be close to a waterfall or running water.

- Try to avoid putting your pond in a fully shaded area.

- On the other hand partial shade is a good idea from the fish's point of view.

- In larger ponds where there are no plants (many koi ponds) floating rocks provide shade and protection from predators.

- Some of these floating rock designs are very large for use in large koi ponds and very different in appearance and shape -- koi keepers can remove the floating rocks very easily when they have visitors to their pond.

- The answer that will still allow you to get a good night's sleep will be discussed in some depth later -- it involves using 2 pumps instead of a single one.

- If you do go to the extent of using concrete and building a large and deep pond then make provision for installing a bottom drain in the pond.

- In making approximations the simplest way to do this is to assume the pond is surrounded by a rectangle and then ask yourself what proportion of the rectangle is covered by water.

- Lets say the proportion is 50% and the depth is once more constant at 0.5 metres and the rectangle around the pond is 3 metres long x 2.8 metres wide.

- If the depth is not uniform then use the average depth to calculate the volume.

- Another more accurate approximation can be made by counting the small squares into which the pond has been divided as in the diagram above.

- Each square in the sketch has a constant size.

- As you can see the total squares covered in the total rectangular area is 11 x 12 = 132 squares.

- The total yellow squares must now be estimated.

- I estimate about 21 full squares are covered by the yellow bits.

- If you get a bit different it does not matter much.

- Now count the white squares -- I get 56.

- Knowing the volume of your pond is important if you want to specify other equipment correctly.

- Once again if you are not sure seek help.

- While considering pond volume 1,000 litres of water is a good volume to hold about 1 kg of fish.