Why Goldfish Turn White

8 Reasons Why Goldfish Turn White

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Most goldfish enthusiasts are aware that these pets are not always gold. Goldfish come in a great variety of colors, even black, even white. Some goldfish start as one shade, but then seem to mysteriously whiten over time. Why is that?

There are a number of reasons why a goldfish turns white, or a near-white. They can range from genetic to environmental, from diet and health to plain ol’ stress.

A goldfish turning white doesn’t have to be a bad thing ~ though sometimes it’s a sign that your pet indeed needs medical attention. Sometimes it’s vital to get that medical help immediately, a strong reason why it’s important to keep an eye on your goldie’s behavior and appearance on the daily.

We do get asked a lot about the whitening of goldfish. To help address the matter, we put together this list of the reasons goldfish might turn white ~ and some things you could do about it.

Summary of Reasons Goldfish Turn White

  • Light (or lack thereof)
  • Insufficient diet
  • Natural genetics
  • Aging
  • Illness
  • Stress
  • Oxygen deficiency
  • Parasites

1.   Light and Goldfish Shades

Goldfish scales and other exterior parts are kind of like the skin in human beings, in that they respond to the amount of light received. As with your tan, a goldfish exposed to no light, or hardly any light, will lighten up in color.

Over an extended period of time, they could end up white, or nearly white, all over! (We should note that some types of goldfish are naturally white).

Still, goldfish fans might notice that those that live in outdoor ponds or natural water bodies end up colored quite brightly. Outdoor goldfish get plenty of sunlight.

2.   Diet and Goldfish Coloring

As with all animals and water life, lack of needed nutrients will alter the appearance of goldfish. Goldfish can require more than just the pellets or flakes bought in stores.

Notice that your goldfish is very slowly lightening in color? Consider supplementing the diet with algae wafers, particularly nutrient-rich superfoods like the spirulina algae.

Besides malnutrition, sometimes what a goldfish eats can impact its color. For instance, it is known that goldfish that eat a lot of shrimp can turn a pinkish hue. (This is due to the beta carotene in the crustaceans).

Some goldfish food, in fact, can be marketed to provide goldfish with “color enhancement”!

3.   Goldfish Genetics Impacts on Color

Some goldfish breeds naturally will turn from a bright color like orange or golden brown to white-ish. Much goes into it, including the type of scales (there are three); how much of the chemical guanine is part of their cellular makeup; and the amount or type of chromatophores, cells responsible for the appearance of the scales.

With some colors of goldfish, namely black, color shifting is common. Goldfish color changes are gradual, and not sudden in response to the immediate environment, like chameleons can do.

4.   Goldfish Color and Aging

Just like with us and our hair, goldfish can whiten up as they get older. This coloration change is very gradual and is apparent in very old goldfish.

5.   Impact of Illness on Goldfish Color

This is the one area where goldfish owners should be concerned: if a goldfish seems to change to a lighter hue rather suddenly. This could indicate the presence of illness. Note: if a goldfish is losing scales along with whitening, it’s definitely an illness.

If you notice a sudden color change, also pay attention to the behavior. Rather sudden changes in swimming patterns ~ whether that means getting way more excited than usual, or a change to no movement at all ~ could mean it’s time to seek medical help.

6.   Stress Can Change Goldfish Color

Also similar to humans is the tendency of goldfish to change appearances when under duress. Stressful changes like changing the tank water, or moving the tank to a place with more or less light, can cause anxiety for your goldie ~ and the potential for a change in hue.

7.   Lack of Oxygen and Goldfish Color

Goldfish that appear to be transparent, or semi-transparent, could indicate a lack of oxygen in the tank. A water change of at least 60% of the water could be a quick fix. Or, look into adding a water pump to add motion inside the tank which can generate more oxygen. Totally stagnant water is not good for fish. (Note: never swap out more than 60% of a tank’s water).

8.   Parasites and Goldfish Color

Parasites are a problem for a whole lot of water creatures, goldfish included. For instance, skin flukes are very small, worm-like pests that feed off the skin of goldfish. This causes the fish to excrete mucus, which in turn can be the cause of a change to whiteness.

When to Worry if Your Goldfish Turns White

If a goldfish seems to be turning white, it’s not always time to sound the alarm sirens. Sometimes the process of turning white is a genetic response. While goldfish come in many colors, it’s not uncommon for them to change their hue over time.

Think of it like being born with yellow blond hair, only to have that shade darken over many years to end up brown.

Additionally, the colors of goldfish have been known to lighten up if the environment around them is dark all the time. With less light, or no light at all, scales on goldfish can lighten or even turn almost completely white.

This does not mean to let it fly if they’re white. To the contrary, it is important to keep a daily eye on the appearance of your pet.

If the goldfish turns white in a sudden manner, for instance, it could be a sign of trouble, and something you might be able to address quickly.

Goldfish turning white can tip you off to a health issue, and there are many potentials. If the color change is accompanied by a change in its swimming pattern, for instance, or appetite, it could be an indicator of a health problem.

Causes of Discoloration in Goldfish

The white discoloration could be due to parasites, an infection, or even stress. Sometimes goldfish, and all captive fish for that matter, can get high anxiety from a change of scenery like if you change tanks, or change the scenery inside the tank.

If the color or behavior seems suspect, check the water in the tank, such as the temperature, ammonia, and pH levels. Discoloration could be due to unclean water.

Consider your pet’s diet. Is it getting enough, or proper, nutrition? You might carefully log what you’re feeding it, then consult with a veterinarian with fish expertise, or an aquarium specialist, to ensure it’s appropriate, or what changes to make.

If your goldfish is found to be ailing, you should try to isolate it in a different tank, if other fish are in there. You don’t want one fish contaminating the others.

In this realm, early detection is key. It’s a reason why we always say to keep a close eye on your pet, and look for any significant changes in anything related to it: its exterior appearance, how it acts, how it eats, etc.

Your pet should regain its original color if the diet is corrected, it gets enough light from the sun, if the water’s oxygen levels are adjusted, if it recovers from illness, if any.

Related Questions

Question: Can I protect the color of my goldfish with LED light only?

Answer: While LED or other electric light indoors can indeed keep the color of goldfish, it’s not nearly as effective as plain old sunlight. Remember also that goldfish have personalities, too, and who is really happy when you don’t see the sun enough? Some goldfish caretakers move indoor goldfish into sunny areas, often for short-term exposure. (However, it might be difficult to ensure proper water temperature if a tank is in sunlight all the time).

Question: Can goldfish turn all white with old age, kind of like people lose all hair color over time?

Answer: Yes. Indeed, the oldest fish are all white, but remember that the change should be gradual, and develop over a significant amount of time. Basically, yes, fish can “gray” over time just like humans and their hair. But few humans, if any, have their hair turn gray in a day.

Question: What are the three types of scales on goldfish?

Answer: Metallic, which are shiny and as the name suggests, metallic in appearance; matte scales which are flat and not shiny; and nacreous scales, which resemble tiny pearls.

Question: What are other signs of illness in goldfish?

Answer: Loss of appetite; loss of scales; less active swimming than usual; a distended belly; or changes to muted colors such as black to a soft brown, or orange to pink, all can be signs of goldfish illness.