changing fin colour?

[Stella]

Does anyone know of (healthy) fish that can change their fin colour?

Actually *changing* the colour, not just the intensity, or go from colourless to coloured.

I have had a fish start to change a colour on one of its fins, from orange to green and back again, sometimes visibly changing over a few minutes.

Just wondering if any other fish are known to do this, and why.

[SamH]

My BN's can change their colour depending on their environment. I moved them from a dark grey gravel tank to a "Fruit Salad"/Light Yellow gravel tank and they became lighter. I read that they get "tanned" if kept under bright ligths and go pale if they spend ages in a cave, not sure how true this is though.

[twinkles]

nearly all of my fish change colour, for example the fish in my daughters tank go really pale over night, so when i turn the lights on the guppies, rainbowfish, bettas are faded looking. Once the lights have been on for a bit they brighten up. I had my scheeli killies in a bare tank with only natural light for a couple of weeks, and they went almost transparent, no sign of their normal blue. Within half an hour of being back in their brightly lit tank with black gravel they were full of colour again.

On the other hand i have australes in a bare tank with real weak lighting, and they are as vivid as always, it seems to be the blue and green colours that fade easiest.

I think only the yellow/red/black are actual colour cells, and the rest are some other reflection of the light? That could explain why only some colours fade. The guppies are orange in the morning, blue/green/purple/orange a bit later.

My new angels are the most noticable, they're next to the tv so i watch them alot, i might glance over one minute and their black stripes are gone, so they are nearly white, then a minute later their stripes are back and true strong black coloured, its amazing.

[twinkles]

The difference in the types of cells for different colours would explain why blue fighters show their stripes/bands much more than some colours, i'm told you can hardly see them on red fighters whereas our blue girls change in seconds to the scared stripes if they are having a disagreement, and the dominant one changes to deep bright unstriped colour when she wants to show she's the boss.

[Stella]

It is amazing how quickly fish can lose colour or brighten up. But that is the intensity of the colour.

I mean a completely different colour: my bully's dorsal fin went from orange to green and back again several times over a few weeks.

And not in relation to blending in with the background or lighting either.

Tis weird.

[twinkles]

well if the green is the reflecting of the underlying cells, and the orange is the colour cells, maybe the orange faded away to show the green underneath? Interesting however it happened

[REEVESTA]

nearly all of my fish change colour, for example the fish in my daughters tank go really pale over night, so when i turn the lights on the guppies, rainbowfish, bettas are faded looking. Once the lights have been on for a bit they brighten up. I had my scheeli killies in a bare tank with only natural light for a couple of weeks, and they went almost transparent, no sign of their normal blue. Within half an hour of being back in their brightly lit tank with black gravel they were full of colour again.

On the other hand i have australes in a bare tank with real weak lighting, and they are as vivid as always, it seems to be the blue and green colours that fade easiest.

I think only the yellow/red/black are actual colour cells, and the rest are some other reflection of the light? That could explain why only some colours fade. The guppies are orange in the morning, blue/green/purple/orange a bit later.

My new angels are the most noticable, they're next to the tv so i watch them alot, i might glance over one minute and their black stripes are gone, so they are nearly white, then a minute later their stripes are back and true strong black coloured, its amazing.

You say that the black does not fade when my angels black stripes some times fade and they dont have any more black on them. and then it comes back in a few mins.

[VinsonMassif]

nearly all of my fish change colour, for example the fish in my daughters tank go really pale over night, so when i turn the lights on the guppies, rainbowfish, bettas are faded looking. Once the lights have been on for a bit they brighten up.

This is because it takes energy to maintain their colours. At night no one sees them so they don't need to display the colours. The reserve their energy. Plus predators are more active at night time so displaying colours would be disadvantageous.

[Stella]

My understanding about how the colours can change intensity is that the pigment contracts and expands.

[twinkles]

the black on the guppies doesn't fade i meant to say, the black and orange are their only colours that stay in the dark. But the black on the angels does.

My new angels are the most noticable, they're next to the tv so i watch them alot, i might glance over one minute and their black stripes are gone, so they are nearly white, then a minute later their stripes are back and true strong black coloured, its amazing.

The other colours on the angels change heaps too, the blue-green tints, but i can't be certain if thats just the way they happen to catch the light or if its actually changing with their mood.

[Ira]

I've seen a surinamensis go from silver with greenish highlights to light tan with black stripes and then back over the course of a few minutes. So, yeah, some can dramatically and quickly change their colors. Not as dramatic or quick as say cuttlefish, but definitely noticable.

[Stella]

Ira, do you know what causes the surinamensis to change colour? Aggression, mating displays, environment etc?

[Ira]

Ira, do you know what causes the surinamensis to change colour? Aggression, mating displays, environment etc?

Aggression or mating display, I think it was. The other surinamensis that he was displaying to was a male, but it still could have been a mating display given my tanks long history of homosexual fish.

[diver21]

well not as quickly as described but marble fighters do it, ive got one that ive only had a few weeks and its gone from a fairly celephane fighter to a rather blue/red guy, buti dont think hes gonna change back