koi anestesia

How to anesthetize a koi ? What is anaesthesia ?

How to anesthetize a koi? What is anesthesia?

The word anesthesia comes from the Greek and means “insensitivity“. It is a reversible pharmacological coma. It consists of blocking the tactile and pain sensitivity during a certain time with the help of an anesthetical product.

The anesthesia of a koi is proceeds as follows:


  • Phase I: Loss of balance
  • Phase II: Body immobilization with ventilation
  • Phase III: Body immobilization and ventilatory stop



  • Phase I: Light body immobilization with slight ventilation
  • Phase II: Start of body mobilization and regulate ventilation
  • Phase III: Full recovery of balance

Water temperature is an important parameter in all phases, both induction and recovery. An experiment* shows: The time to reach Phase II is reduced by 50% in water of 26 degrees instead of 15 degrees.

Also keep in mind that the induction and recovery time is higher with large koi than with small koi.


Nevertheless we in Koi Hacienda have noticed, that every koi is a different case. You can have big koi which “fall asleep” quicker than a small koi just because its constitution is different.

Why and for what anesthetize a koi?

Anesthesia is to do when we need to treat a koi and we can not allow it to move or to suffer. That happens when we have to heal wounds, do an X-ray or some kind of surgery etc. It may also be necessary to make a brief anesthesia if you want to make a detailed routine inspection of koi with preventive reason.


How to anesthetize a koi?

The most used products are phenoxyethanol and essential oil of cloves.


It is a good general anesthetic. There are two disadvantages: First, it is difficult to get this chemical product as a private person and second it is usually only sold in large quantities (1 liter to approx. 50 €).


  • 0.6-1 ml for 1 liter

Eessential oil of cloves

It is undoubtedly the most efficiente, inexpensive and easy product to get (in drugstores or online). Eugenol is an oily yellow liquid extracted from certain essential oils that can be used as an antiseptic and analgesic. Eugenol is also found in cinnamon, basil, laurel and many other plants, but only clove comes to be between 70-80% of eugenol.

As it has a low solubility in water, it is usually mixed with 96% ethanol in equal parts.

You can find essential oil of c clove of many brands. Prices range between 3.50 € and 15 € for a bottle of 10 ml or 15 ml. When buying, make sure that the eugenol concentration range between 70-90% (to ensure a good quality and to follow the recommended dosage).

Although most essential oils have dropper, it is safer to use a syringe and measure the amount in ml, as droppers do not have standardized amount.

koi enfermo


  • 2-8 ml to 100 liters (20-80 ppm)
  • 4 ml per 100 litres is considered optimal
  • less than 2 ml per 100 litres has no analgesic effects
  • more than 12 ml per 100 litres is fatal

In natural medicine it is used for its benefits in relieving digestive diseases, muscular, respiratory and skin. In this respect there are still no studies with fish.


How to anesthetize a koi – step by step

  • prepare a container with enough water (the full body of the koi must be under water) and the respective dose of analgesic
  • if you don’t use pond water, ensure that there is no important temperature difference between the water in the container and the pond
  • catch the koi and introduce it into the container
  • observe how the koi lives the different stages of induction of anesthesia. Do not leave the koi unobserved
  • when the koi has reached Phase III (floating, not breathing and no tactile reflexes) you can take it out of the water to make the necessary treatment
  • in the case that the koi “wakes up” before completing the treatment, you can enter it again in the analgesic water (especially the gills) for a short time
  • completed the treatment, the koi is introduced into a floating net in the pond so it can recover. If you would release the koi immediately into the pond, the koi could get damaged by crashing against any object in the pond as it has not yet 100% recovered its natatorium balance.
  • at Koi Hacienda we have experienced that some koi enjoy human touch and like this special treatment: instead of letting it recover in the floating net – we keep the koi in our hands moving it slowly forward and backward causing the water flow opens the gills and water can more easily enter. Thus it recovers easier.
  • once fully recovered its natatorium balance, you can definitively release the koi


How to anesthetize a koi ? Here a video which shows the different phases of anaesthesia:



De la Gándara, F.; Raja, T. y García-Gómez, A.

Instituto Español de Oceanografía. Centro Oceanográfico de Murcia. Planta de Cultivos Marinos.

Carretera de la Azohía s/n. 30860-Puerto de Mazarrón (Murcia-España). e-mail: fernando@mu.ieo.es


Utilización del aceite de clavo, Syzygium aromaticum L. (Merr. & Perry), como anestésico eficaz

y económico para labores rutinarias de manipulación de peces marinos cultivados A. García-Gómez 1, F. de la Gándara y T. Raja

Planta Experimental de Cultivos Marinos. Centro Oceanográfico de Murcia. Instituto Español de Oceanografía. Ctra. de la Azohía, s/n. E-30860 Puerto de Mazarrón (Murcia), España. Correo electrónico: antonio.garcia@mu.ieo.es





como seleccionar buenos koi

How to select good koi

Workshop: How to select good koi

This workshop aims to train the koi lover to make it easier to select even young koi. You will have a theoretical part in which we inform about varieties and families of the koi and the history and characteristics of some varieties. There will also be a practical part to apply the newly learned.

  • Sunday March 27, 2016
  • at 11 am (approximately 2 hours)
  • pre-registration necessary (until March 25)
  • limited places
  • free workshop




Koi hunting

Koi hunting

The previous trips to Japan to select koi have been exciting, but this year … this year I got a slight idea of ​​what the gold-digger felt at the time of the gold rush. And Thierry … Thierry for the first time in 10 years of Koi Hacienda has really lived the word “koi hunting”.

Many people think it is a simple trip to Japan and go from breeder to breeder and choose what we like.

It is not. It’s like going hunting. You never know what you’ll find. Our plans – our shopping list – is purely indicative.

Let me give an example: in 2014 we had the opportunity to select tancho tosai with Torazo (which is most famous for its tancho). In 2015 they were sold out and we came back without anyone. This year, there were some tancho left … but only a few … and we will have them.

Another example: traditional breeders as Chogoro … all our purachina come from Chogoro who continuously gets the big prizes of this variety. This year we arrived and he informed us that he had sold the whole lot of purachina in November last year. A Chinese wholesaler … the WHOLE LOT. We were extremely lucky and thanks to the friendly relationship we have with him (see pictures) he left us 50 purachina of his special lot.

So the word “hunting” is very appropriate … you know that you’re going to an area where there are plenty of animals that you want to have, but until you don’t have them really in your hands, you do not know what you are going to get.

We started our “koi hunting” with the breeder Toshio Sakai. We went out with jumbo nisai (= 2 years koi) kohaku and sanke WITH CERTIFICATES of the breeder. 

koi tosai Toshio Sakai

Koi hunting: Nisai at Toshio Sakai

There are some koi that perhaps can not win a prize, but they are special. My attention was caught by “Marilyn” … as Marilyn Monroe … the super American diva. I’ll tell you … I will write a blog about all the special koi we found.

The next day we went to choose the tosai (=  1 year koi). I leave the link to see the video (preparing the pond in the traditional way to select the tosai, takes about 7 minutes):

Although we have seen precious nisai with Torazo, we limited ourselves just to buy the maximum number of tancho maximum as last year we could not get any. We accepted the few tancho he offered us and complemented them with kohaku.

A pleasant surprise was breeder Otsuka. Not particularly famous but with good koi at good prices. Because of their size (10 to 12 cm) 120 Tosai fit in a box so we can offer many varieties at an affordable price.

What a joy to find again the same quality of koi with Hiroi. Last year we bought tosai gosanke and ginrin gosanke and they grew extraordinary. They will arrive quite big (15 to 18 cm), which means that not many will fit in a box … so … “first come – first serve”.

grupo gosanke

Koi hunting: Tosai Gosanke at Hiroi

The most funny hunting – for me – was with Chogoro. This day we have had a terrible weather – a mix of snow and rain combined with wind pushing this humidity into your body which will not vanish all day. He took us to his “secret place” where he keeps his high quality koi. He showed some goshiki which left us with our mouth open.

goshiki Chogoro

Koi hunting: High quality Goshiki at Chogoro

Unfortunately we could not buy them, because in Spain there is still no market to pay thousands of euros for a 2 year koi. Especially a goshiki which would change its appearance over the next few years.

Chogoro purachina

Koi hunting: Chogoro & Koi Hacienda

We went to another greenhouse and we started the selection of tosai. Hours …. And hours have been there on our knees trying to pick the best koi of about 3,000. Unlike the others, Chogoro did not let them see one by one, selecting as Cinderella … they were all in one big net. When I saw a nice one – whoosh – gone again … Kujaku, goshiki, Hariwake, sakura ogon, Kin Matsuba, ginga daya …


Koi hunting: Tosai at Chogoro

We laughed a lot as we had chosen some koi where Chogoro – with a big smile – said those were not good (when they really were great). And we had to pay attention since occasionally he tried to take them away.

Then we could not resist buying some nisai both goshiki and purachina:

goshiki purachina

Koi hunting: Nisai at Chogoro

To cut a long article a little bit down, I do not enunciate to the many breeders we have visited and we left without buying anything.

In 2015 we did not visit him, but in 2014 we bought some koi and we already liked this breeder: Yagenji. Definitely one of the most organised and hygienic koi farms (not counting large ones as eg Dainichi). As we were missing Showa, we got there a mix with lots of wonderful Showa and the rest other varieties.


Koi hunting: Tosai at Yagenji

With Marudo we “fished” some 2 years chagoi, karashigoi, soragoi and yamabuki:


Koi hunting: Kawarimono and Yamakuki at Marudo

We will also have tosai of Marudo: 30 sanke, 20 matsuba gin, 20 asagi and … a few units of a very seldom variety … I will write in another blog.

And … finally … Hirasawa. Mr. Hirasawa is already about 70 years old, but he can not live without his koi. The koi are his life. Hirasawa family has large greenhouses in the mountains managed by  his children, but he stays with the two greenhouses that are connected to his home.

We knew that here we would take hours and we were really there from 14h30 to 18h30 !!! With Hirasawa we bought nisai, sansai (=  3 years koi) and exceptionally tosai.

Here only photos of Hirasawa and nisai … I want to keep some secrets and some suspense ?


Koi hunting: Hirasawa and his traditional polaroid camera 

To finish this post with good news: Some of you have followed us on Facebook and have seen the picture of “SOLD OUT” when we visited Dainichi. This sign was referring to the category of Dainichi Showa we brought last year.

We did not want to disappoint our customers and have made the big effort to bring again Showa from Dainichi of an even higher category. 

NEW KOI for sale  from 15th APRIL on (10.00 – 14.00 hours)

Saturday 16th and Sunday 17th ALSO OPEN (10.00 – 14.00 hours)

Reservation only possible for koi from 2 years on.