While the most important factor that determines your goldfish’s color is genetics -- which you can do nothing to change -- the proper environmental conditions and diet will help make their colors more visually appealing. It is especially important to maintain proper water chemistry and to provide access to natural sunlight whenever possible. Nevertheless, inexpensive “feeder” goldfish will rarely attain good color, so you should always start with quality fish from a knowledgeable source.
Carrots for Color
Substances called carotenoids produce the orange color of common goldfish. Goldfish cannot produce these chemicals internally; they obtain them via their food. Many commercial goldfish foods are fortified with carotenoids and are marketed as color-enhancing. Quality versions of these foods will help improve the color of your goldfish. Aquarists who make their own food include plenty of carotenoid-rich foods such as peas and carrots. It may take up to four weeks for dietary enrichment's effects to manifest.
Swimming in the Sunshine
Goldfish often exhibit their best coloration in outdoor ponds. According to FishChannel.com, the combination of consistent water conditions and access to natural food sources helps to bring out the existing colors in goldfish better than any other method. A 1998 study published in the “Fisheries Science” journal found that goldfish who were fed carotenoid-rich diets and had access to direct sunlight exhibited more vibrant color that similarly fed fish who received only indirect sunlight.
Cleanliness Cures the Colorless
Water quality is an extremely important factor that helps to determine goldfish color intensity. Poor water quality is frequently a problem with goldfish kept in small bowls without a proper filter or enough space. Poor water quality not only causes dull color, it leads to more serious health problems as well. Help your fish look their best by housing them in a 20-gallon aquarium with a suitable filter.
Goldfish often change color over the course of their lives. While this is usually a normal event, you should contact your veterinarian to be sure the color change is not related to illness. The progression of the color change can vary from one color form to the next and from one individual to another, so it is difficult to predict what type of color change you should expect from your fish. You can get a better idea of what your goldfish’s ultimate color will be by purchasing fish that are at least 12 months old.
- FishChannel.com: Common Problems in Goldfish
- Fisheries Science: The Accumulation of Pigments From Paprika in the Integument of Goldfish Carassius Auratus
- Fisheries Science: Evaluation of Color Intensity Enhanced by Paprika as Feed Additive in Goldfish and Koi Carp Using Computer‐Assisted Image Analysis
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