Chromis swimming erratically for hours after lights out

Sierra_Bravo · May 4, 2018

I've caught this behavior several times. Every once in a while one of my blue/green chromis - not sure if the same one - will swim in an erratic manner all over the tank throughout the night. I've never seen it do this during the day, and it isn't triggered by anything in particular as far as I can tell. I am not shining a bright light into the tank or anything like that. Tank lights go down to moonlight around 8 PM and off completely at 10 PM.

He was doing this at midnight last night and I checked again around 4 am - still going at the same frenzied pace. Is there an explanation for this?

eatbreakfast · May 4, 2018

Do you have hermits, other crabs, or serpent stars? I would be willing to wager something disturbed it in it's nightime hiding spot.

looneywun · May 4, 2018

could be something picking on it.

Sierra_Bravo · May 4, 2018

eatbreakfast said:
Do you have hermits, other crabs, or serpent stars? I would be willing to wager something disturbed it in it's nightime hiding spot.

Hermits, brittle and serpent stars yes. I would imagine it could be spooked by having a bristled tentacle rub up against you when you were sleeping in the middle of the night. . . I would be.

If that's the case I wonder why it wouldn't settle back down in a reasonable time frame? Four hours is a long time to be running for your life.

I was concerned the little guy was going to die of exhaustion.

Lor · Oct 11, 2018

Sorry to bring up an old thread, but care to share what happened to the chromis, mine is doing the exact same thing.

Sierra_Bravo · Oct 11, 2018

Lor said:
Sorry to bring up an old thread, but care to share what happened to the chromis, mine is doing the exact same thing.

He continues to do that to this day, although much less frequently. As near as I can tell it must have something to do with light, possibly someone turning on the room lights after its been dark for a while. Other than that I do not know.