Many pond enthusiasts start their interest with a small pond with Goldfish, Comets, and Shubunkin’s and then introduce a few Koi to provide a colourful addition to their collection. Koi will not achieve their full potential in small ponds and are likely to eat all the water plants, and tadpoles. In small ponds the water temperature and chemical composition are prone to sudden changes which Koi do not like, and their size, shape and health will likely to be affected by limited swimming area and a lack of depth.

Koi Pond Size

Koi need a healthy environment with clean well oxygenated water that can sustain them as they can reach up to sizes of one metre in a heated pond, and on average 60 centimetres. A minimum standard Koi pond should ideally be at least 4 foot deep and hold over 1000 gallons.

The shape of the pond can be left up to your imagination with traditional ones being kidney shaped, however the sides of the pond should go almost straight down rather than tapering. Koi get the most exercise by swimming up and down in the pond so it is recommended to go to a depth of 6 feet in places.

Finally, while it is tempting to economise, it is well worth building a Koi pond as big as possible to let your collection grow, as many Koi keepers find they end up building two, or more ponds before finally arriving at the perfect set up

Pond Construction

Koi Ponds with simple shapes and flowing curves allow a good circulation of water and avoid dead spots. The ideal method although the most expensive is a construction in concrete blocks, with a rendered surface and finished in fibre glass and sloping of the pond base towards the bottom drain. It is perfectly acceptable to use a Pond Liner and have a gravity fed side drain. When fitting the liner, care should be taken to pleat and fold the corners carefully to minimise the chances of debris becoming trapped. The corners can be fixed down flat with special mastic tape or glue to give a good finish.

Pond Filters

Once you have decided on your construction you need to work out roughly how many gallons the pond will hold so you can get the correct equipment. Koi produce large amounts of solid waste, so your ponds filter system must be able to remove solids from the water. The filter comes with nylon brushes, plastic media or a vortex that slowly spins the water and allows larger, heavier particles to settle out.

The filter must be easy to clean and if it is fed from a bottom drain must have a valve to shut it off from the pond,or if its a gravity fed filter system incorporate a drain for easy flushing to waste that can be used to carry out regular water changes. We recommend that when you are feeding your Koi regularly to clean you filter system once a week.

All filter boxes have biological filtration which utilises bacteria to break down the ammonia produced as a by-product of the fishes metabolism. The bacteria live on the surfaces of the filter media and break down the Ammonia excreted by your Koi.

A Koi pond biological filter is the vital life support system that will keep your fish alive. It is far better to spend your money on a good Pond Filter system.

Pond Pumps

You need to choose your pump carefully and you will need to work out the water capacity of your pond. The pump must be chosen on the basis of the amount of water flow it will provide at the point where the water goes into the filter system, or returns to the pond. As a rule the size of you pump should be able to turn water volume over every 3hrs with no fish, turnover every 2hrs for Goldfish, and turnover every hour for Koi.

There are a huge amount of Pond Pumps available, so we always recommend having a good look around until you find the one that meets your needs the most.

Pond Air Pumps

Both your fish and the biological filter require large amounts of oxygen to thrive, especially when you are feeding heavily and the weather warms up. It is a good idea buy a Pond Air Pump so you can place air stones directly in the filter system to provide oxygen for the filter bacteria as well as in the pond itself.