There are many reasons why people fall in love with Koi and want to keep them as pets; not least because of their outstanding beauty which brings joy to any observer but also because of their calming and soothing effect which have been known to reduce stress and bring down a high heart rate. In this article, as a beginner Koi enthusiast, you will learn how to choose Koi for purchase to stock your own Koi Carp pond.

Firstly, make sure you get as much information as possible on the Koi fish from a reputable breeder or pet shop owner. Staff there should be knowledgeable about the fish so do not hesitate to ask questions. For example, is the fish from a local source or imported? Imported Japanese Koi are usually the best quality. If you can, visit a few Koi fish farms to decide who to buy Koi from. Check the conditions under which the fish are kept – their Koi pond water for instance should be clear and odorless, supplies sold in their shop should be of good quality.

Koi fish come in a large array of unique color patterns. No two Koi have exactly the same markings and color. It is important to know that the color of a young Koi will change as it matures - usually the colors become darker so worth bearing this in mind when you are selecting.


Look out for signs of a healthy Koi. Koi fish are sociable creatures. It is normal to see them interacting and socialising with each other. If you see a Koi swimming alone or hiding somewhere in a corner, avoid that one as it may not be the healthiest.

A healthy Koi will swim smoothly and efficiently. There should be no jerking movements, no twitches or any kind of unsmooth motion. Gills should move rhythmically and evenly. If the Koi is infected with gill flukes, it will breathe through only one gill or have redness around their gills.

A healthy Koi’s body is thick, gently tapered and well-defined. Their scales lie flat with no lesions. Make sure you see no visible signs of any damage, ulcers, or discolored spots anywhere on the fish.

Cost-wise, young Koi will be cheaper to buy than adult ones and show-quality adult Koi will be even dearer ie the latter can cost thousands of dollars but a young Koi of 3 to 4 inches (7.5 to 10 cm) in length may cost between $5 to $10 each.

As far as knowing how many Koi fish to keep in a Koi Carp pond, there is no overall agreement amongst experts on what this figure ought to be. The answer in all likelihood, is that it all depends on how efficient your filtration system is in eliminating fish waste products, nitrates, ammonia and how high the aeration level is in the pond. The pond itself should, in any case, hold at least 1000 gallons of water and be a minimum of 4 foot in depth with plenty of cover for the fish.

Now before you rush out to buy your first Koi, it is important that your pond has been built and a good filtration system is already up and running ready to receive its first occupants.


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