Fish lean in the dark?

[Mr. Awesome]

I have had two yellow fish (I have not idea what type) that lean to one side when the light is turned off but straighten when the light is turned back on. I have a twenty gallon tank and it sits on an even surface.

 

[Andrew]

i dont see any problem with the behavior. unless they start swimming upside down or floating!!!!!

 

[rebecca200020002001]

if you meen they lean there heads down, thats them sleeping;

they sleep like dolphins. they shut on side of the brain down and rest it and then they swop so one side is always awake

 

[Jessica B]

they're probably sleeping