Been thinking about "do fish sleep" a lot lately. They definitely do, at least most fish!
Last night hubby went to check on Mr. Blue betta and his two new shrimpy friends, and Blue had stuffed himself into the java moss and was sound asleep, and the shrimp were racing around like crazy shrimp
Mr. Red was up behind the filter.
Miss Betta was on the intake in her fluval spec 5g...
Mr. Algea in our 20g tank often sleeps upside down underneath our mushroom decoration that we finally got after eying such a thing for a year. And our panda cories just pass out sometimes.... hehe. The pygmies and the habrosus must sleep too. So cute...
I found this article, also:
Do fish sleep? | The Fisheries Blog
Feel free to share any fish sleeping stories or whatever