[["They sleep at night, but beta fish do not have eyelids - so, even when they're asleep or resting, you may think they're still awake.", 674.0], ["When asleep, Betta Fish become still, with their eyes open because of their absence of eyelids. Betta fish may lose their color while sleeping (it's their natural form of self-defense), & they can sleep in different positions: curled up like a cat, on one side or even vertically with the head down.", 157.0]]
how do betta fish sleep
animals,fish,goldfish