Fish Turning White And Dying – Why And How To Prevent It

There are several reasons why your fish turning white and dying. Even though it’s common for fish to change hue and color as they age, this might occasionally indicate environmental or health problems. Let’s learn more about our topic in this post!

Why My Fish Turning White And Dying

Fish Turning White

When a dead fish becomes white, it can signify that your tank’s water conditions or location aren’t ideal, endangering your remaining fish. Here are some of the most common reasons behind this issue.


Your fish’s waste and the digestion of their food both release a gas called ammonia. Ammonia poisoning, also referred to as new tank sickness, occurs when your aquarium comes with excessive ammonia. Fish are at risk of dying if the ammonia level in their tank exceeds 40 ppm (parts per million).

You can find out whether there is an ammonia issue in your fish tank with ammonia test kits. It is recommended to keep the test kit in the tank for a minimum of an hour following testing. 

This way, the kit will have enough time to measure the ammonia content of your tank. Suppose you take the test kit out before the required time; you won’t receive a reliable reading.

Water Temperature

The water in your fish tank needs to be kept at the right temperature to maintain the fish’s health. Because a fish’s blood and gills are responsible for controlling body temperature, it needs water generally at the same temperature.

Stress will result from the fish’s inability to regulate its body temperature due to too cold or too hot water. Your fish may become ill due to stress, which could be fatal.

pH Level

The pH level of the water must be just right for fish to survive. All fish share this characteristic, albeit the exact details depend on the species. An ideal pH range for the majority of tropical fish is between 6.8 and 7.8.

Meanwhile, pH levels in the range of 7.0 to 8.4 are necessary for goldfish and cold-water species. Rapid changes in water quality can also be dangerous or lethal.

The pH levels can fall out of balance for many reasons, such as mineral traces present, failing filtering systems, the surplus of ornaments, etc. Once the pH level gets low, the fish will become white and perish.


fish with filter

When fish start to become white, the filter may be a problem. It’s possible that the filter is not working as it should, which is why impurities are getting into the tank. On the other hand, the ecosystem of the aquarium may suffer from a fish tank filter that is excessively powerful.

Therefore, choose your filter carefully. Some factors that can help you decide are the tank size, your fish’s traits, the quantity of fish in the tank, etc. Also, it is advisable to inspect your filtration system to make sure it is in good working order.

Low Levels Of Oxygen

A fish’s body soon loses its vibrant hue once it dies because the organs and blood stop obtaining oxygen. This is a completely normal practice that shouldn’t raise any issues. 

However, if a fish turns translucent white just before it dies, it means there isn’t enough oxygen in your tank, which suggests the fish suffocated to death.

You may increase the oxygen levels in your fish tank by adding more plants and providing a substrate that supports plant growth. Reducing the amount of fish in the tank is also a good way to ensure your fish get the necessary amounts of oxygen.

What Are Other Appearance Changes When Fish Die?

a sick fish

If your fish manifests one (or more) of these signs, it might indicate the approaching death of your beloved pet: cloudy pupils, sunken eyes, or labored breathing. Besides, one of the most obvious red lights is the loss of color.

When a fish dies, some fish turn white, while others lose all color, going from vibrant to drab. The usual culprits are environmental variables, as mentioned. 

Another plausible explanation is stress, which may result from several reasons, such as difficulties with other tank mates, inappropriate water temperature, soiled water, etc. 

Although it is not always simple to determine when something is wrong inside the tank, keeping an eye on your fish’s behavior and performing frequent water tests will help preserve their color and health in general.

How To Prevent Your Fish From Turning White And Dying

Give Your Fish Tank Enough Sunlight

Fish require some kind of sunlight to be prolific and healthy. Even certain fish require sunlight for the development of skin pigment. If they don’t get enough sunshine, their scales gradually become lighter and eventually vanish.

Thus, it would be best to place your tank where it may get up to 12 hours of sunlight per day. However, keep in mind not to place the aquarium in direct sunlight as it can increase the water’s temperature and lead to major issues.

Avoid Overcleaning

white fish

Cleaning your fish tank is important since it will make sure that trash is taken out, unwanted growth is stopped, and the filter is working properly. Still, overly frequent tank cleaning might also make your fish stressed out. This could cause your fish to perish, and as it does, it will gradually start to become white.

The proper schedule to clean your tank is only one or two times a month. You must immediately change 10–20% of the water in your fish tank, depending on how frequently you prefer to clean it. Also, avoid changing more than 40% of the tank’s water at once since doing so could harm your fish and the aquarium.

Feed Your Fish Correctly

Providing your fish with a correct and balanced diet is crucial. While some fish may require live food like worms or shrimp, others may prefer algae or do just well with regular fish flakes.

Once you’ve established the proper diet for your fish, be careful not to overfeed them. Overeating can harm your fish’s health, just like it can do to any animal.

Wrapping Up

Now you understand why the fish turning white and dying. It is crucial to keep an eye on the color of your pet fish as the coloration frequently indicates the fish’s level of health. Also, consider water quality, cleanliness, and diet regularly to keep the fish’s health at its best.