Why Did They Turn Blue?

[Amunet]

Just took a look in to our 125 a little bit ago. Turned on the room light to look in the tank, and noticed that the peppered cory were blue.
I've never noticed them changing to this color before the other times I've disturbed the tank at night.
Is this common? I mean not that I think I have super fish or anything lol. Just curious to know why their colors would change like that?
I know the skunk cories in the tank get duller when the lights go off.
The tiger barbs get duller as well. The rainbowfish get brighter colors when lights go off.

I took a couple of photos. The blue color faded the longer the light stayed on.
The color wasn't picked up very well when I took the photos. When I first noticed the blue color, it was very obvious and very intense. It was a true blue color.
All of them looked like they were resting.

without flash

with flash

 

[Coryologist]

I took a couple of photos. The blue color faded the longer the light stayed on.

One man's "blue, is another man's "green." I have seen this with C. paleatus on numerous occasions. This also happens with blue, purple and green Moscow guppies all the time. Depending on your water parameters and the type of lighting you use, these color shifts are quite common and very temporary, as you have already witnessed. As a photographer of fishes, I can tell you that even capturing what looks like a blue sheen is usually due to the white balance being affected by daylight in the room or the color temperature of the artificial lighting. As always - your mileage may vary. - Frank

 

[mixmaster jay]

mine do the same thing

 

[Amunet]

That's pretty neat. This is just the first time I've noticed it.
And they were definitely blue in color. Not green or anything like that. It was a true blue color. Very deep and intense and obvious.
As I said, the camera didn't pick up the color very well. I would've turned the tank light on, but didn't want to startle the fish before I could get a photo of them. So unfortuantly had to suffer poorer quality photo.

I'll have to keep an eye out for it again