Koi fish sinks to the bottom when sleeping. This kind of fish sleeps for no fixed time. If you see it standing still in one place, only the gills open and close, indicating that it is asleep. It should be noted that we must pay attention to the distinction between sleeping and lying on the jar. Plying on the jar is a manifestation of physical discomfort, which indicates that fish may get sick. It is best to change water, heat up and add salt, and give it simple treatment, otherwise the situation may deteriorate and even endanger life.

1. The water quality is too poor: Many novices change the cleaning filter materials too fast when changing water, which makes koi fish unable to adapt to the new water quality quickly and lie prone. This can also be said to be caused by stress reaction. In this case, filtration and sterilization can be carried out, the filter can be fully opened, and nitrifying bacteria can be cultured well. In this way, the water quality will become clear and koi fish will become active.

2. Entering a new environment: The newly entered koi carp does not fully adapt to the new water quality, and will lie prone and be lazy all day. This situation will disappear naturally after they adapt to the new environment.

3. Bacterial infection: The new koi carp has not been disinfected, which may lead to cross infection after entering the cylinder. In this case, it is necessary to disinfect the fish tank, cultivate nitrifying bacteria and explode oxygen to improve the water quality and keep the suitable water temperature. In this way, the phenomenon of koi carp lying on the cylinder will disappear.