A curious axolotl fact is that they do not have eyelids, so they sleep with their eyes open, making it difficult to tell when your pet axolotl is awake or asleep. Knowing if axolotl is awake or asleep at night is more difficult.

However, as a nocturnal creature, it is active at night and sleeps during the day. Some signs that show when an axolotl is asleep include stillness of gills and other body activities. It will also most likely retreat to its hiding space when it wants to sleep.