Goldfish ecology and breeding information site


Spawning Methods and Precautions

If you have kept goldfish for a long time, you may want to try to breed them. However, if goldfish spawning is not done with care, there is a high possibility that the goldfish will weaken. In this article, I would like to explain in detail the method and precautions for spawning.

Time of spawning

The goldfish spawning season is from the end of March to around May.It is no exaggeration to say that the suitable time for goldfish to spawn is very short. Medaka have a suitable spawning period for half of the year, which is very short in comparison. However, there are exceptions, such as goldfish that spawn in the fall. Goldfish born in the fall are called Fuyugo (winterling) and often do not grow well.

Suitable age for spawning

Goldfish have an age at which they are best suited for spawning.The best age for females is about 2 to 3 years old, and generally speaking, 5 years old is the limit.If you try to spawn goldfish that are too young or too old, the number of eggs will decrease and the fertilization rate will drop, so it is recommended that you spawn them at an appropriate age.The appropriate age for spawning in the case of males is 2 to 4 years old goldfish.

How to distinguish between male and female


Goldfish begin to show the pursuit star when it is time to spawn.The pursuit star appears only in males.The pursuit star appears on the gills, pectoral fins, and other areas on the front of the body. It is important to note that this is often mistaken for white spot disease.

goldfish used for sucking up to one's parents

Selection Criteria


It is better to have good parents to lay eggs and breed fry than to just let them lay eggs and breed fry, so I will explain the criteria for selecting parents. The first is,The body's gala and color must be well-defined.Each breed has its own characteristics, so it is best to choose the best goldfish for your type of goldfish as a parent. Second,The size of the female's body must be somewhat large.The larger the mother's body size, the more eggs she will hold in proportion, so try to select the largest body size possible.

What to look for when choosing

Spawning is a very taxing activity for goldfish. Therefore, the possibility of death after spawning is very high. Please do not choose goldfish for spawning carelessly, but carefully consider the choice.Since the goldfish spawning season is very short and many people are in a hurry to spawn, we recommend that you select and prepare which goldfish you will use for spawning well in advance.

Spawning Flow


First,When it is time to lay eggs, the males begin to chase the females. The male will then peck the female in the abdomen area with his mouth.The female then begins to spawn, thinking that this is a signal to spawn. If there are plants in the water, the female rubs her body against the plants and begins to release her eggs. When the eggs are released, the male, who is nearby, immediately inseminates the eggs to fertilize them.

Post-spawning measures

Spawning is not the end of the process. After spawning, it is very important to take care of your goldfish.Most goldfish die during the spawning season because they die after spawning.Be especially careful with females that have finished spawning, as they are often weak. After spawning, it is advisable to change the feed to something more easily digestible for about three days. If the female does not have a good appetite or is not very energetic, take immediate action.

Points to keep in mind when spawning

What are the precautions in letting the eggs lay eggs?The number of females and males should be 1:2.It is almost always the female goldfish that die after spawning. During spawning, the males rub against the female's body as they spawn, so naturally the female's body may be damaged to the point where the scales are sometimes removed, so if you are thinking of spawning goldfish, it is better to keep the place where they spawn and the place where you always keep them separate.