Male & Female Koi. Breeding Koi, Goldfish


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Page Summary:  Does your favourite koi go by the name of Fred or Freda and are your sure Fred Koi is not Freda Koi after all. For koi breeders this question is no laughing matter but for you and me it probably doesnt matter that much. Let's be content for the koi themselves to sort out the gender question. During the spring breeding season the male koi can be likened to a bull in a china shop with the female koi being somewhat desperate to avoid the loving attention of more than a single male koi. This seems to me to be a bit like, at least some, humans behave.

Male or Female Koi?

For you and me deciding the sex of koi is difficult to say the least with one exception and that's when the urge to breed in Spring takes over

Yes of course we would like to know because for one we've all been told female koi grow bigger than male koi.

This of course is very subjective and is a function not only of the koi but the owner's behaviour with respect to the koi in the pond.

It is apparently true that most winning show koi tend to be female.

It's next to impossible to determine sex of smaller fish which are not ready to breed.

For dealers specialising in growing and selling koi it's vital that the sex of koi are known as soon as possible.

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Spawning Brush

Spawning brushes (normally green in colour... to represent weed colours0 float in the pond water.

Fish eggs adhere to the spines. After spawning brush is placed in an area where adult koi cannot access.

Male and female koi sex differences

Literature suggests that male koi tend to be more lithe looking, more fit, more sporting, more like a speeding bullet with clear cut lines. They apparently tend to be somewhat on the shy side like many koi keepers themselves. But I can't be sure of that and frankly I'm not sure the person who told me that is sure as well.

It's in spring when the male koi become obvious to us. Male Koi take on their breeding behaviour and often appear to have small white bumps on the head. Apparently female koi do not develop this symptom.

Seperating Koi Eggs and Fry... Spawning Brushes for Ponds

Spawning BrushIn spring when loves comes around the koi will need somewhere to lay their eggs. In a natural environment eggs will adhere to submerged aquatic plants but in a koi pond there are not always plants because the koi tend to eat them. If the koi keeper wants to breed koi then the pondkeeper must arrange to harvest the eggs and this is best done by using a specially made soft fibrous brush. The koi eggs are sticky and adhere to this soft spawning brush. Once the fish have completed spawning the brush should be removed and placed in a separate holding area (containing pond water) otherwise the fish will eat the eggs

You'll be amazed at how simple it can be to breed fish with the help of Bradshaw's Spawning Brushes. You'll need one mature female and at least two males.

Read this message I got from one of my newsletter subscribers:

"Morning Tony, Yesterday my wife and myself sat next to the koi pond and watched the fish go crazy close to the surface of the water and around the polystyrene floating net you told me to make. I thought it was because of the fry in the floater or the food that gets washed out of the net, but after a while there was hundreds of eggs stuck on the net, just as you said it would happen." Regards, Phil Müller

Put the brushes one above the other at the edge of the pond. Spawning usually occurs in the early morning after a night of flurried activity and can take several hours. Most of the eggs will stick to the brushes which can then be taken out of the pond and put in filtered water of the same temperature. If the eggs are not separated from the adult fish they may be eaten.

Hatching should take around 3-6 days and then the small fish should be kept separate until they are large enough to be introduced into the pond.

Filter BrushesDo not confuse these brushes with filter brushes used effectively in pond bio filters (click link to view the filter brushes)

It's quite easy to make a holding are by creating a floating fine mesh net attached to expandable polystyrene for example.

Other articles about koi and fish pond care in winter

Pond Heaters. Heating koi ponds winter growth feeding benefits

Koi pond heating using gas electric in UK temperature control

Bringing fish and pond and water out of winter into spring

Koi goldfish pond covers over winter. How to look after pondfish

Over-wintering koi goldfish hibernation cold freezing water ice

Koi pond heating using gas electric in UK temperature control

Should I heat my new koi pond this winter. What temperature?

Temperature swings. Koi Goldfish Feeding & water temperature

To Feed or not to feed your pond fish or koi or goldfish

How Do I care For My Garden Fish Pond In Cold Winter

Frozen Koi Ponds & Fish Ponds. Ponds Freeze in Winter. Pond Care in Freezing Winter Weather

Interpet Koi Pond Test KitWhat the Does pH of Koi Pond Water Mean? Should I measure Pond pH