Extremely Weird Neon Tetra Behavior

[Rosenweiss]

Hey guys, so I'm stumped about something my 12 neons do.

When I turn off the light at night, they literally throw themselves against the edge of the tank. Always the same side. They will just toss their bodies towards the side, sometimes close to the top, for about a minute until they chill out. Any idea why this might be? Are they shocked by the light going off? Other than that they swim, shoal and eat entirely normally.

Am: 0
Nitrites: 0
Nitrates: 10
pH: 7.6
Temp: 78

Any insight would be greatly appreciated.

 

[Barliman]

They might be panicking, though mine don't do that. (They have their own weird behavior.) Do your lights have any sort of transitional or twilight setting? It would be interesting to see if that helped.

 

[Rosenweiss]

I don't have, I want to upgrade my lighting soon, but right now I don't have that. But I have noticed that if the room lights are on, they aren't as freaked out.