Duncan Griffiths


Duncan Griffiths Copyright © April , 2003, D, GRIFFITHS, ALL RIGHTS RESERVED


If a koi hobbyist keeps go-sanke long enough it only a matter of time before he/she comes across the skin disease called Hikui.

Hikui is a skin ailment that affects the Hi or red colour on a koi and only the Hi.

Typically if caught early it displays an orange/yellow colour blemish on the skin, if left it will eat right through the Hi till its gone and white is exposed, as is the case in the example contained here in.


Scientific research has not pin pointed the cause of this disease but research has found cancer type cells contained in samples of Hikui, but it is not proven at this time that has anything to do with the disease and speculation continues with cause being listed as bacterial or viral as well as it being a form of cancer, but as said non of this is proven.


Some Japanese breeders believe it to be hereditary and if a breeding pair start producing off spring that display Hikui they will n o longer breed from that pair.


This article is not to debate the reasons for the disease Hikui but to offer a cure for it, I hasten to say this not the only cure out there but one that the author has goodsuccess with and is relatively cheap and requires no real expertise.

The crux of this cure is dependent on preparation of the infected area along with careful drying of applications applied to that area,

It must also be noted that the Cauteriser will in effect bleach out some of the red colouring, this may or may not grow back dependent on the severity of the case


Items needed include

Cauteriser paste

Oraheasive powder

FriarsBalsam or G7 liquid sealer or similar

Some form of anaesthesia

Cotton wool

Cotton buds

Optional a hair dryer


The first picture shows the infected areas outlined in black


Hikui can be seen on the subject as three separate areas on the head to just behind,

You will notice that the first area, the Hi has indeed been eaten away, while the two other areas are displaying the typical yellow/ orange sores that are more usual with this disease.


After sedating the koi, the first thing to do is agood clean up of the area, with any dead or dying scales to beingremovedand apply rocal or similar to help with the task of cleansing.




After this the area must be wipe perfectly dry at this point you can use the optional hair dryer set on cold ( being careful,wet hands and electricity donít make very good companions)


Once dry start applying the Cauteriser with a cotton bud taking care not to overlap, as this will bleach the area of some of the colour.



Once the Cauteriser applied apply the Oraheasive powder to the painted areas to cover all the Cauteriser


 Spread the powder out with a cotton bud and blow away the excess what left will be stuck onto the Cauteriser forming a crust


Once you are happy with this apply the Friars Balsam or G7 sealerout of a pump action plastic spray bottle till covered or you could drip the dealer off a tooth pick onto the site to cover, the Oraheasive powder will absorb some of the sealer before you start to form a film over the treatment, this is quite normal



Allow to dry well you could use you hair dryer for this again set on cold being careful with the electrics.

 Once dry release the koi back to the pond. The medication will stay in place for one week and no further treatments will be needed so do not rush the job make sure you do it right first time





Cauteriser is available from Paula Reynolds at Lincolnshire koi health priced at around £5/6 a pot and will lasts for years.

Cauteriser was not made for Hikui that was the authorís adaptation, it was made for mouth rot and fin rot and just about anywhere you would normally put Potassium permanganatepaste,whilst great care should be taken not to get it in contact with delicate areas such as gills, this Cauteriser is not as aggressive as PP paste.


G7 sealer is also available from Lincís koi health at around £7/8 and again has more than one application.

Friars Balsam available over the counter at you local pharmacy, 50 ml£1.50


Oraheasive powder was made for weeping cuts ETC, in humans and is available from your pharmacy over the counter (non prescription) although may have to be ordered.or from Kusuri products 25 gm £5, again this stuff goes a long way.