A brief history of Koi

Nishikigoi, or Koi as they are more commonly known, are the national ornamental pond fish of Japan. They are relatives of the goldfish but are far more colourful and grow a great deal larger - sometimes up to 90cm in garden ponds.

Koi originated back in 800AD, where they were bred for food by isolated farmers in what is now the Niigata Prefecture, North West of Tokyo.
Eventually, colourful specimens were noticed in the early farmers’ ponds and, from the 1800’s, breeding for colour became a highly competitive pastime among the Japanese peasant farming community.

These magnificent fish came to be referred to as "living jewels" and are now enjoyed as much loved (and long lived) companion pets in garden ponds all over the world.

Questions About Koi

If you're thinking about having your very own Koi pond, you'll find that it's a reasonably straight forward hobby, but there are one or two things you'll need to know before you get started. Your local Koi Society Branch members are always keen to help a new Koi keeper and will give you "hands-on" help and advice. Here are some questions which newcomers to the hobby most commonly ask:

How Big Does My Pond Have To Be?

Koi can be kept in a pond of almost any size but, in smaller ponds, their growth will be stunted and their health and colour impaired as they grow larger. A good rule of thumb is to start with a pond no less than 2-3 metres long, 1-2 metres wide and at least 0.5 metres deep.

With the right filtration, this will take about ten healthy twelve-inch fish. In larger ponds, more fish can be accommodated and they will grow larger and faster and in better health. For large fish, allow about 500-1,000 litres of pond water per fish. Many people are now converting unused swimming pools to Koi ponds.

Do I Have To Filter The Water?

Absolutely. Your filter and pump should run all year round, 24 hours a day. Today’s high efficiency pumps keep electricity costs to a minimum. You can make your own filter quite easily or you can chose one of the proprietary Koi pond filters that are available. The key is to ask for advice BEFORE you get started on your pond and filter.

How Fast Do Koi Grow?

In properly filtered water, a small fish of 5cm will usually reach 12cm in two or three years and some fish grow a good deal faster. They usually reach their maximum size of around 65-80 cm within
5-10 years and can live to a ripe old age of more than one hundred years.

What Do I Feed Them And How Often?

Koi pellets are readily available from pet shops and from the Koi Society. They are an excellent basis for feeding, but variety of diet will improve the health, colour and growth of your Koi. They love cooked vegetables (especially pumpkin and peas), as well as salad vegetables, wholemeal bread and cooked porridge. Animal fats should always be avoided. Your Koi's appetite will vary with the water temperature and they can be fed 4-6 times a day in the heat of summer. Unlike any other pet, they can go for several weeks without any food at all!

What About Maintenance?

This depends on you. A well designed pond and filter needs far less maintenance than a domestic swimming pool - usually less than ten minutes per week. However, a poorly designed pond or filter will be a real headache for both you and your Koi. That's why it makes sense to get proper advice from the Koi Society BEFORE you start.
The Koi Society of Australia has published an excellent book called "Koi Keeping in Australia" which is an absolute "must" for beginners to the hobby.

Can I Breed My Koi?

You certainly can. In fact this is an area of Koi keeping that is an enduring source of pleasure and satisfaction. Your Koi will spawn naturally in your pond, usually at the approach of summer. But Koi don't make great parents and usually eat their own eggs! That's why a second smaller pond is needed for raising the babies.

Help When You Need it

Remember that the Koi Society is there to help its members. All you have to do is ask. Contact the Koi Society in your area to make sure you get the right advice BEFORE you start on a new pond. That way, your new Koi pond will give you and your family years of pleasure.

Convenient Locations

The Koi Society of Australia has seven branches, conveniently located from Newcastle to Shoalhaven. Meeting times and contact telephone numbers are listed below.


Pumps, food, books and other supplies are available from your local KSA branch at discounted prices for members.

Families Welcome

Koi keeping is a hobby for families and yours can become a member of the Koi Society for about fifty cents a week. children are welcome at meetings and need little encouragement to take an interest in the hobby.

KOI Auctions

The KSA has Koi Auctions about six times a year so that members can buy and sell fish at bargain prices.

KOI Shows

All branches have regular fish shows and trophies are awarded. There is also an annual show for smaller fish and a major national show each May which attracts over 15,000 visitors. A Japanese judge is flown to Australia for this event.

Pond Tours

All branches have regular pond tours so that you can inspect other members' ponds and gardens and swap ideas.