It is better to raise fish in the sun. The growth of fish needs a certain amount of light, but it can't receive direct light for a long time. Usually, special aquarium lamps can be prepared to supplement its light. It only needs to be exposed to the sun for 4-8 hours a day, and it needs to be turned off at night, so as not to affect the rest of fish. Appropriate light can not only promote its growth, but also induce its hair color, which is very important for some ornamental fish.

1. Increase the temperature difference: One of the most obvious disadvantages of direct sunbathing is that it will increase the temperature difference. Because basking in the sun will raise the water temperature, and the temperature will drop at night, so the temperature difference between day and night is relatively large, which is very unfavorable to the health of fish. Therefore, it is best not to put the fish tank in the sunny place, but to control the temperature with a heating rod at ordinary times.

2, easy to explode algae: Algae in fish tanks are also very sensitive to light, and long light time can also promote their growth, and once they are not well controlled, they will explode algae. Algae explosion is particularly dangerous. Algae will not only occupy the water environment, but also consume oxygen. Once they die, they will pollute the water and endanger the survival of fish.

3, lower dissolved oxygen: Sun exposure will also reduce dissolved oxygen in fish tanks. Because light will increase the water temperature, and the upper limit of dissolved oxygen in water body is closely related to the temperature, just like the fish in the pond will float in summer, the temperature of the fish tank will rise, and the overall dissolved oxygen will also drop, which is not conducive to the fish breathing.