Koi pond

Koi pond, building a perfect hobby

If we talk about a Koi pond, it is about a pond with koi, the national fish of Japan. A koi is a special domesticated version of common carp. They are beautiful fish to look at. Koi need a duly maintained pond to guarantee health of these valuable fish. The technique applied in koi ponds should therefore be inspected and maintained regularly.

Make a koi pond deep enough

Depth of a koi pond should be at least 60 in. This necessary to prevent large fluctuations in temperature of the water in winter, so that koi may hibernate. Reason why a koi pond is deeper than for example an ornamental pond. In that part of a pond where koi are swimming you should not grow any plants. Reason is that Koi are herbivores. They will consume all plants they will come across in the pond. An exception are plants in floating baskets which prevents them from eating the plants. As plants in a koi pond can not keep water clear, a solid filter equipment should be used. If necessary, in combination with a separate marsh plants area. Often additional arrangements are made, such as pond heating or a UV-C Filter.

Koi will reach a length of about 28 to 32 in long. This is why a koi pond should be large enough for these fish. Principle is one koi per 1,000 litres of water. Subject to the size of a pond and the materials applied, investments may increase considerably. You should bear this in mind if you want to build a koi pond. However, if you to make a hobby of your pond, a koi pond is the perfect choice.

Building a Koi pond

To build a koi pond you will have to choose between cost involved, the well-being of fish and convenience for yourself. A thorough planning in advance is of great importance. Drafting this planning you should consider the following items:

  • Position of the koi pond
  • Form of the pond
  • Depth (minimum 60 in)
  • Size of the pond (and the number of koi)
  • Filter systems (place, size and set up)
  • Pumps
  • In and outlets for the pumps and overflow
  • Placement, if required, of a skimmer (floating surface of an exhauster, including pump)

Koi are a have load for pond water. Pond filter and pond pump are therefore important to bring the quality of the water to the level and to keep it at that. Another possibility would be natural filtration of the koi pond. In this system plants have been separated from koi, so that they can not be eaten up. A so-called helophytes filter (also referred to as plant or marsh filter) is connected to koi pond and will purify the water owing to the action of plants and substrates. Yet it is advisable to place always an additional filter system. Bottom sludge is disastrous for clear water and unhealthy for koi.

You might also use a bottom drain. It is some kind of a drain, connected to the sewers, which serves to remove and transport dirt deposited on the bottom directly. The drain should be installed already when laying out the pond, namely at the deepest point of the pond. Especially for overloaded koi ponds this is a popular method to discharge waste material.

Maintenance koi pond

Maintenance of a koi pond does not really differ from that of a normal pond. In autumn blown in leaves have to be removed from a pond. This will prevent leaves from decaying on a pond bottom. Organic waste material on the bottom will increase the risk that a pond will acidify. These are no proper living conditions for koi fish. Besides, it will increase the risk of algae problems.

The best thing you can do is to remove regularly all fallen leaves from your pond. You should preferably do this using a scoop. The same holds good for decaying leaves or sludge on the bottom. Convenient is also a special pond vacuum cleaner or suction dredger. It is not wise to suck out the whole pond annually, trying to clean the bottom. By such effort you do not only remove all kinds of useful aquatic animals but you affect also to a considerable extent the household bacterial community , which is exactly in winter very important indeed. Besides it leads to much stress for the koi present.

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