Small goldfish can bask in the sun, which can not only sterilize and disinfect, but also improve their physique and reduce the chance of getting sick. Breeders can often bask in the sun. Although small goldfish can bask in the sun, they can't accept too strong light, so breeders need to avoid the midday sun. It is best to choose the sunshine in the morning or evening, which can make small goldfish receive natural light without excessive temperature. Small goldfish can't bask in the sun for too long, about 2 hours a day. When basking in the sun, the breeder also shields them from half of the sun, so that they don't want to have shelter after basking in the sun.

If the environment where small goldfish live is full of natural light, it is not necessary to turn on the lights. Because they also have their own work and rest time, at night, they will enter a state of rest. If there is plenty of light during the day and the lights are turned on at night, they will remain highly tense all day. In the long run, if they can't have a good rest properly, they will have an impact on their health.

If the environment where small goldfish live lacks natural light, the breeder needs to turn on the light to supplement them with light. Because the lack of light may make them dim in color, in order to ensure their ornamental value, it is best for breeders to turn on the lights for 3-5 hours every day.