What Does It Mean When Your Goldfish's Scales Start to Fade?

Too Little Light

• Much like human skin, goldfish scales contain special cells that release pigment when exposed to light. If a goldfish is kept in darkness or very dim light, pigment will not be released and the color of the goldfish will fade. In the absence of light, some goldfish may become almost completely white. If exposed to light again, a faded goldfish will gradually regain pigmentation in its scales. Sunlight, as opposed to artificial light, is more effective for stimulating pigmentation in goldfish.

Not Enough Pigment in Diet

• Goldfish acquire red pigments, called carotenoids, from their food. Some carotenoid-rich foods that goldfish consume in the wild are shrimp and spirulina, a type of algae. Some commercial fish foods contain carotenoids and other color-enhancing ingredients. Read the labels to find a fish food that is made for specifically for enhancing the color of scales, and check the ingredients for spirulina. Feed your fish regularly to maintain their health and coloration.

Illness

• A variety of fungal, bacterial and viral infections can cause the color of a goldfish to suddenly fade. Much like human illness, goldfish illness can be recognized by a combination of symptoms. Look for other signs that your goldfish is not well, such as spots or marks on the body, swelling, red gills or bleeding. Look for behavioral changes as well, such as if your fish has stopped eating or swimming. Observe your fish carefully and also be sure to maintain a clean, healthy environment for your fish at all times to help it retain coloration.

Some fading is natural

• The scales of all goldfish will fade somewhat with age. The lifespan of domestic goldfish can vary dramatically, but a healthy and well-cared-for goldfish may live several decades. At a certain point during a fish's lifespan, scales may fade, much like human hair turns gray. This may occur quite suddenly. Blues and blacks tend to fade more than oranges and reds. Some hobbyists claim that keeping older fish in warmer water helps reduce this effect, but this is unproven.