Goldfish generally lay eggs in spring and autumn every year, and spring is the main breeding period. Under suitable conditions, they can lay eggs up to six times a year. The main factors affecting their spawning are temperature and feeding conditions. Under normal circumstances, healthy female fish can generally lay eggs 2-3 times, and as many as 4-6 times, with an interval of about 10 days. If the female fish is weak, this time will be prolonged accordingly. The number of spawning is also related to the changes of external conditions such as age, physical condition and water temperature. If the conditions are right and the water temperature and quality are stable, they can also lay eggs in winter.

To hatch goldfish eggs, the water temperature should be controlled first, and if it is kept at 15-16 ℃, small fish can be hatched in about seven days. Then gradually increase the water temperature, first keep the water temperature at 18-19 ℃ for four to five days, then keep the water temperature at 20 ℃ for three days, and finally raise the temperature to 25 ℃ for two days. Attention should also be paid to prevent sharp changes in water temperature during incubation. It is necessary to control the water temperature and stabilize it in a fixed value. In case of water temperature change caused by uncontrollable factors such as excessive light or sudden climate change, it should be properly adjusted and corresponding measures should be taken.