Koi do NOT grow to the size of the pond they live in...

They grow to the size of their genetic bloodline characteristics... They may start off as cute and small BUT...

How large do big Koi grow?!

It's a good question if you're starting off in the hobby. As is continually advocated on this site, we try and encourage you to see the end picture, not the immediate short term 'I want a Koi pond scenario'.

Koi size and shape and largeness

Koi can get large. In fact they can get HUGE! You need to realise this and so does your pond!

As with most things in life it is the female Koi that are most prized because of their superior body shape pattern. Females tend be more 'bulky', at the risk of sounding politically incorrect. But this 'bulkiness' is highly sought after, especially when the weight is carried in all the right places.

A large female Koi can reach over a meter and at the All Japan show these days a Koi needs to be there or thereabouts to stand a chance. At these lengths, the mass is around 12 kg, but personally I think it's closer to 20 kg looking at some of these small floating red and white 'whales'...

It's not to say that the males are excluded - far from it. It's just that the tendency is for females to have the better body volume/shape.

A Koi's size is NOT solely determined by the size pond it lives in, as is a common misconception. Whilst it is true that a small pond will inhibit growth to a certain extent owing to the Koi's innate sense of self preservation, the bloodline and genetic makeup of the Koi is far more significant.

That said, it must be borne in mind that the Koi's environment also plays a significant role in it's growth. Factors such as food are of enormous importance. A healthy growing Koi needs healthy food and I'm an advocate of as much live food as possible - earth worms, larvae etc. Whilst it's not possible to feed all of this every day, as often as you can will have massive benefits for your Koi... At the very least get ultra high quality Koi food from us - our Koi food is brilliant (even if we say so ourselves)..

Big Koi are also known to excrete growth inhibiting hormones when there are little Koi in a pond with them. Not much is known about this but it makes sense in that the bigger Koi, with the greatest odds for survival will tend to try and keep their dominant position for as long as possible. In a smaller pond, with a mix of large and small Koi you might see this phenomenon and if it is happening with your prize Momotaro or Dainichi bloodline Tosai (one year old Koi) that you want to see reach Jumbo (large size 80cm+) you would be well advised to move it to a pond of more similar sized Koi.