Today most modern gardens are not complete unless they have a koi pond to show off these beautiful ornamental fish.
There are a few practical considerations that must be kept in mind! when building a Koi Pond the main one is planning ie the size of the pond, where in the garden to locate ie best kept away from large trees to avoid damage from tree roots, and how many koi you plan to keep.
Depth of the koi pond will also be a main consideration as the min depth idealy would be 4ft which will help to keep extreme tempature fluctuations to a minimium which is a lot deeper than your average garden pond. The reason for depth is shallow ponds will cool and heat quickly. Which is can be a risk to the health of the koi. The pond should have a raised edge to avoid run off from the garden which may contain chemical or fertillizers.
Maintenace should be taken into account at time of constuction to make this part as simple as possible a bottom drain is a must for the removal of fish waste and debri. Depending on size of pond you may need more tha one bottom drain. Skimmers built into pond walls will help remove debri and leaves from the pond surface.
Filtration should be a major factor at planning stage, as this is the heart of the koi pond. Bigger the filtration the better you can never over filter but can easily under filter. So please don,t scrimp on the filter side. Specialist filtrations should be purchased or built for koi ponds ie bead filters or Nexus Eazy filters.
Other major factors to consider when building a koi pond would be budget as you will need a decent Pond Pump, Ultra Violet, Air Pumps, Switch boxes, Pipe work and fittings, possible landscaping once pond is built and not forgetting the expense of the beautiful Koi.