Different colors of goldfish
At birth, goldfish don’t have any colors, they develop them later in their life. The color of goldfish is influenced first by the environment and conditions in which they live, starting with the light: fish living in well-lit tank or pond will be more brightly colored in comparison to others. This is why goldfish raised in a dark environment (for example in a river or in a very deep pond) may not have the most beautiful colors.
Why do goldfish change their colors?
Your goldfish’s color has changed – 4 common reasons:
- Water issue or stress
- Change in the amount of light or water temperature
- Young fish (dull color) transitioning into adult coloration
- Genetics or old age
Stress and/or poor water quality can make goldfish paler: if you think that something is not quite right with your goldfish, you should get a test kit that measures ammonia and nitrites. Make sure that your tank is well filtered and do regular water changes.
However, some varieties of goldfish do naturally change color several times during their life, which is perfectly normal. Some fish also gradually go paler with age (sometimes turning completely white). If your water quality is good and your goldfish is otherwise healthy, you probably don’t have to worry about any progressive change in your fish’s color.
Goldfish colors and color combinations
Goldfish colors and their combinations depend on the varieties.
Among others, some of the most common are red, orange and yellow, white, black, bronze, or combinations of two or three colors, calicos.
Some foods have supplements that reinforce certain colors: carotene and spirulina (a type of algae) are two well-known examples.
There are three main types of pigments: black (melanophores), red (erythrophores) and yellow (xantrophores), which can be combined. Added to this is the function of guanine, which forms a layer underneath the scales, which, depending on its nature, will produce different effects by reflecting light: the skin and colors of fish explained.
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Some varieties of goldfish change colors several times during their life. This is normal. Pale fish can be fed more food containing carotenes. Also, some branded foods have been specially made for this purpose: Hikari, Sera, Tetra and others offer excellent products for this purpose.
Photos 1 and 2 : goldyfk@fishkeeping.co.uk (licence CC BY-NC-ND)