The Pond Blogs - Week 6 - How to Build a Garden Pond Part 3

Pondkeeper

The pond blogs – 29/06/2011

Garden Pond - Part 3

This is the third and final instalment of how to build a pond.  So far we have looked at choosing; size, location and type of pond; as well as how to dig, prepare the ground and lay the liner. This week will look at the final stage, how to finish off your own water garden paradise.

Finishing

Once you have let your pond liner to settle you need to trim off excess pond liner and underlay, leaving a minimum of 30cm overlap for anchorage.  Next you need to finish the pond with some sort of edging.  This is normally done with stones or paving, but this is by no means a restrictive list.  Ideally you would leave a small overhang to protect any exposed liner from direct sunlight, even though most liners are now UV resistant.  Another method would be to use grass turf, which may overhang and touch the water.

Add equipment and plants

Now the basic pond is built you need to think about equipment and plants.  Depending on the type of pond you have decided to make the question of filtration, pumps, and plants comes up.

Filtration

For any normally sized garden pond, a good filtration system will be important, as the body of water is not really sufficient to create a natural cleaning system.  There is the old fashioned but much more complicated way of designing a gravel bed filter, which is basically feeding the water through layers of gravel in a specially designed holder pond, either bottom or top fed and then taken back to the main pond.  A much simpler way is to use a pre made filter.  These come in two di9fferent types; a pressurised filter or a box filter.  The later provides the best filtration as it is gravity fed the water only slowly moves through the filter and sediment has time to fall out of the water.  The benefit of a pressurised filter is that they can be burried and placed away from the edge of the pond (a box filter must be higher than and next to the pond).  Unfortunately, although a pressurised filter solves the issue of having a large plastic box standing out next to your pond, due to the fact that the filter basically works on the concented of forcing water quickly through sponges and some biomedia they do not provide a good enough filtration for Koi or a highly stocked fish pond as the sediment has no chance to fall out of the water.  Generally today most filters also come with a UV Unit inbuilt.  The UV unit uses a UV bulb to clarify the water by breaking down green water (algae) and other such organisms

Pump

Now you have decided on one of the two basic types of filtration, you need to look at how big a pump and filter that you need.  As a rule for a normally stocked fish pond (excluding koi) you would look to turn the water over between once every 2 hours and every 1 and a half.  If you have a Koi or a high fish stock, it is important to turn the water over at least once every hour.  It is also important to match the pump size to the filter size, a sa pump that is too big for the filter will cause the filter to overflow.

Pond Plants

The addition of pond plants can have a number of positive benefits and are strongly recommended for any pond.  As we have discussed in the first part of ‘how to build a pond’ they oxygenate the pond, and help to prevent green water and blanket weed.  They also act as a natural filter as well as providing an aesthetically pleasing aspect.  It is important to develop a biologically balanced pond, and then you will avoid the majority of pond problems as well as attract more wildlife. 

Some good suggestions for newly built ponds were made on BBC Gardeners Question Time, and included;

Hornwort, which acts as a very good initial oxygenator and a James Brydon Water Lilly, to provide surface coverage. 

Around the pond in the marsh area to provide some colour to the planting a couple of emergent plants were recommended such as the Caltha or ‘Marsh Marigolds’ for spring colour, an Iris for Summer colour, and the Pontderia or ‘pickerel weed’ for late season colour.

These can all bve planted in your pond using planting baskets and socks

For all your pond building and maintenance needs follow these links

• pond liners
• pond pumps
• pond filters
• filter and pump sets
• pond kits
• pond vacuums
• pump to filter hoses
Next week, we will look at general pond maintenance.  All the products you need can be found at www.pondkeeper.co.uk and so long as orders are placed before 1pm on a Thursday you can have all the equipment ready for the weekend.  Please also follow Pondkeeperuk on Twitter and Pondkeeper.co.uk - Armstrong Direct Ltd on Facebook to be kept up to date with all the latest news and offers from the world of Pondkeeper.co.uk