A Guide to Modern Koi Pond Construction

Sand filter

Some koi-keepers consider that adding a sand filter to the system after the main filter does polish the water and removes a lot of the small particles which have passed through the filter.

[Sand filter in position]

 This photo shows one type of sand filter in use on a pond system. This is situated in a garage alongside a filter system, and allows for easy maintenance.

[drawing of sand filter]

[drawing of sand filter]

[List of parts]

[Multi-port valve]

 This photo shows a close up of the multi-port valve which is similar for all makes of sand filter.
This handle is shown in the normal running position. At the bottom, under the handle, is the rinse position. The handle should then be moved to rinse before returning the handle to the run position.
The pump must be stopped each time the valve handle is moved.
The pressure gauge is important as it shows when there is back pressure on the pump caused by the sand getting dirty.

[Sand filter in South Africa]

The drawing above shows the general layout for installing a sand filter into the system. The unit is installed right after the main pump and before other items such as UV, heater, etc. This prevents any excess pressure on these units if the back pressure should build up in the sand filter.
For the above reasons it is important to use high pressure pipework, and these units require a high pressure pump such as a swimming pool pump.

[Removing the sand]

In Capetown, South Africa, many koi-keepers there were using a swimming pool sand filter as their main filter unit. In these cases they used 6mm gravel as the media so that it did not clog up easily as the normal silica sand would do.
It must also be remembered that swimming pools are very common in that country so spare parts are easy to obtain and are relatively cheap.

Check out Changing the sand in the sand filter.

This page updated January 2004
Finally we will look at Waterfalls.
This website started with a booklet which I made up originally for the help of those members of the BKKS - South Wales Section who were intending to start building a koi pond, and as the website has expanded more information and articles from other people have been included. This is for general guidance only, and we do not take any responsibility for problems that might occur by following these ideas. It is important that you check out everything in your area, and check on local laws and rules that may apply.
Home - Pond descriptions - Pond heating - Pond construction - Koi health - Projects - Products - Photos from Japan - South Wales section - Letters - Links - Guest-book - Statistics - New - Forum
Website Copyright © 1999-2009 Koi Cymru