Koi Fish Information Centre

Your pond may be OK for the koi right now, but as they grow they will need more room than you have in the pond you are planning to construct. This means that you will either expand your efforts with this pond and make it bigger, or you will build another, bigger pond, and, perhaps, join the two together with a stream or other such water feature. Keep in mind that your little 3″ fish can grow to 47″, meaning they will have a hard time turning around in your 4′ width pond (puddle, now ).
My last full sized pond was built about 20 years ago, and for the liner, I used a material called Permalon which was fairly thin, but relatively impervious to punctures. I do not know how available it is today. I never did use UV, but it can be helpful in certain situations. The water pump needs to have enough oomph to push water through the filter to a level where the waterfall will work, and be able to turn over the pond at a rate of 5-6 times a day, or a bit more, since you will be rapidly overcrowded in your pond. You do not mention a filter in your list. A good one can be built relatively inexpensively and can use bioballs for biological filtration. Use of foam as a particulate filter is also suggested, either in the pond itself, or in a filter box with or without the bioballs. The foam will also serve for biological filtration.
For under the liner, I have found stone dust to be a good material to use. Old newspapers also serve well. No need to get fancy. No one will ever see it once it is covered. Any plants you use will need to be caged to keep the koi from eating them.
Plumbing. Go with the PVC. Buried wisely, you will not need to worry about traffic over it. Copper, when there is enough of it, can be toxic to your fish. Do some reading on this. You mentioned a skimmer earlier, and now I know what you mean, a foam fractioner. That, along with the UV, should you still decide to use it, should be in the filter area, which will be, somewhat, hidden from viewers of the pond. (Judicious plantings around that area and end of the pond will help.) I have never used a bottom drain, so I cannot comment on that, but you may wish to use a pool skimmer type arrangement as well to remove the larger debris from the water before it hits the filter or pump.
\Steve//

Category: Philippines Internet Koi Society