Why Fish change color, Koi, Goldfish, etc

[tinycat]

I keep seeing posts where color changing fish are confusing their people. It is not arbitrary, there is science behind these changes. There has been lots of research done on the topic, so I thought I'd link some research papers and articles.

"The skin color of koi is primarily determined by genetics. However, the breeding environment conditions, such as temperature, oxygen and salinity, can directly or indirectly affect pigment cells and pigment particles, causing changes in skin color"

Correlation of skin color and plasma carotenoid-related metabolites of ornamental koi carp under temperature fluctuations​

"the seasonality affecting the skin color of koi in this study included changes in water temperature, daylight length, atmospheric pressure, dissolved oxygen, and light intensity, but not food supply"

Targeted metabolomics revealed the seasonal plasticity of skin color and pigment metabolites in ornamental koi carp​

Genetics, stress, diet, sun exposure affect color according to The Pond Guy

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Please add additional info about things you've noticed affect the color of your fish. Seasonal changes, temperature, diet, things like these research papers suggest? Your own anecdotal stories?

 

[Lisak1]

Randomness. I don't know how else to describe it but we have one that changes colors frequently from orange to white. Most recently it's only gone to a very light orange, but in the early days would go from full comet orange to white several times a season. Some years it doesn't change at all. We know it's the same fish because of the size and unique fin pattern.

So "random" is my addition to the discussion. haha!

 

[GBBUDD]

I keep seeing posts where color changing fish are confusing their people. It is not arbitrary, there is science behind these changes. There has been lots of research done on the topic, so I thought I'd link some research papers and articles.

"The skin color of koi is primarily determined by genetics. However, the breeding environment conditions, such as temperature, oxygen and salinity, can directly or indirectly affect pigment cells and pigment particles, causing changes in skin color"

Correlation of skin color and plasma carotenoid-related metabolites of ornamental koi carp under temperature fluctuations​

"the seasonality affecting the skin color of koi in this study included changes in water temperature, daylight length, atmospheric pressure, dissolved oxygen, and light intensity, but not food supply"

Targeted metabolomics revealed the seasonal plasticity of skin color and pigment metabolites in ornamental koi carp​

Genetics, stress, diet, sun exposure affect color according to The Pond Guy

--------------------------------------------

Please add additional info about things you've noticed affect the color of your fish. Seasonal changes, temperature, diet, things like these research papers suggest? Your own anecdotal stories?

There are certain breeds that change more than other fish like Ochiba in my experiance to not change there colors maybe darken or lighten but the pattern remains a constant. Now Beni goi can be an absolutely stunning fish as far as patterns and colors go but they are now will they change but how much. I have two currently and one had patterns on it's side that were wild it looked like a dragon and on the other side was a swan. Both in black surrounded by red well their both gone now , the overall shape is there but the sharp outline where anyone looking could see is now so different. Showa, Sanke and Shiro you can be certain they will change; there's little doubt in that. but Goshiki, Yambuki, Chargoi, are a few that stay true to their colors and patterns,
But as was mentioned diet and conditions in each pond can vary greatly a fish that you buy in Japan will more than likely get much much darker when it comes here to the United States the water is that different.
Most fish like showa and sanki if you see gray on them and you look close it will probably look like this gray is under a layer of white and in time that black will work it's way to the surface and could become completely different from what you see today, so there's a little crystal ball that's needed often you can see a fish that is outstanding in color and pattern to have it completely change and you never would have spent that kinda money on. "ask me how i know"

 

[waynefrcan]

My koi colors are fading to white some more than others. These are USA and Canadian bred. The only real Japanese koi is not.