Black rainbowfish?

[Waffle toaster]

I just bought 2 boesemani rainbowfish from a fish store that had just came in and hadn't been put in tanks yet. 4 more will be coming in next week, so I might get more. Thay started out as steel grey like they,re supposed to, and it seemed like they were developing more colors as the day went on. But when woke up this morning, the one that I think is female had turned black around her face and gills area, and a little on her side. Is this normal? Is she sick? Is she stressed? I just got her yesterday, and I don't want anything bad to happen to her.

 

[George9]

I just bought 2 boesemani rainbowfish from a fish store that had just came in and hadn't been put in tanks yet. 4 more will be coming in next week, so I might get more. Thay started out as steel grey like they,re supposed to, and it seemed like they were developing more colors as the day went on. But when woke up this morning, the one that I think is female had turned black around her face and gills area, and a little on her side. Is this normal? Is she sick? Is she stressed? I just got her yesterday, and I don't want anything bad to happen to her.

My boesmanis would change color very fast depending on their mood. Mine got black when they were really mad. Also, their coloring got really dark at night and lightened when the lights came on. I think it because she was sleeping, or because she's stressed in her new home. Just watch her, I think it's normal.

 

[Waffle toaster]

Thanks, the black spots faded as it got lighter, and then she turned darker this morning, and now the black spots are fading again. I think the black spots were just there because it was dark in the tank for so long.