Purple tang color change when sleeping

[Sierra_Bravo]

After lights out and when he settles to sleep, he'll turn a very pale shade of purple grey with just a horizontal bar of his regular purple down his mid-sides.

I searched for this to see how common it was but didn't find much info. I did read they'll pale when stressed, but this occurs every night at rest and if the lights are turned back on he'll color up within 30 seconds or less. I'm guessing this is a camouflage response?

Pardon the dirty glass on the QT:

 

[4FordFamily]

This is completely normal for purple tangs, all zebrasoma genus tangs, most other tangs to some degree, and many other fish as well!

 

[Sierra_Bravo]

Thanks for the reply. I asssumed it was a normal response; I just couldn't find much about it. I'll probably do a little online research tonight as I'd like to know the biologiocal mechanics behind how they actually alter their color. Do they possess chromatophores or is it by another process? Pretty neat.

 

[4FordFamily]

I’m honestly not sure how, I’d love an explanation myself. I suspect inactivity leads to color loss, like blood rush makes us flush but that’s a complete stab in the dark.

Thanks for the reply. I asssumed it was a normal response; I just couldn't find much about it. I'll probably do a little online research tonight as I'd like to know the biologiocal mechanics behind how they actually alter their color. Do they possess chromatophores or is it by another process? Pretty neat.

 

[FreeEnergyReefer]

Boy amni glad this was here. Almost freaked out. Just gotta new baby purple tang from my lfs seen this for the first time just now. Mine has a black patch like in the pic and it looks like a tiny whit patch above the black one only at night. Pretty cool

 

[homer1475]

You think thats odd, you should see a mandarin sleeping. They look like their dead with absolutely 0 color.

Quite a few fish loose their color, or fade coloring when sleeping.

 

[Joem820]

It certainly freaked me out the first few times i turned on the lights. Not gonna lie, if i don't think about it i still have a few seconds of panic.

 

[Patientman]

Isn't this a "protection" mechanism" for night … becoming less noticeable to night predators by loosing their bright colors?

 

[OrionN]

Thanks for the reply. I asssumed it was a normal response; I just couldn't find much about it. I'll probably do a little online research tonight as I'd like to know the biologiocal mechanics behind how they actually alter their color. Do they possess chromatophores or is it by another process? Pretty neat.

'cuss no one take picture of their fish in the dark.