Koi reproduce by laying eggs. Koi usually reach sexual maturity when they reach 60 centimeters, and then they mate and reproduce on their own, laying eggs to hatch small fish. If during artificial breeding, in order to promote the reproduction of koi, you can choose to breed between 3 and 10 years old. Choose koi that are healthy, disease-free and injury-free as broodstock. Around May every year, when the water temperature is stable above 16°C , male and female koi can be selected and put into the spawning pool in a ratio of 1:3.

Precautions for koi to lay eggs:

1. Before koi lays eggs, it is necessary to prepare the container needed for spawning. It is best to put a container in the container. If there is no fern, you can use other aquatic plants or old hemp silk instead.

2. If a female fish ovulates, a male fish must release sperm so that it can become a fertilized egg. If the male fish does not release sperm for a long time after the female fish ovulates, you can try artificial sperm ejaculation. Gently press the male fish's abdomen with your thumb to expel semen.

3. After the fish eggs are fertilized, you can wait for the fertilized eggs to hatch. If you encounter rainy weather, it will be more difficult for the fertilized eggs to hatch, and some will become moldy and hairy. The owner can move the fish tank to a ventilated area to reduce mold growth.