Why Are My Saltwater Fish Losing Their Color?

Why Are My Saltwater Fish Losing Their Color?


If you have been in the saltwater aquarium hobby for any length of time, you most likely have seen a pale fish or a fish that used to be vibrant and colorful lose that color and eventually die. Unfortunately, this happens far too often.

There are many reasons why saltwater fish can lose its color.

1. Stress

Stress is considered the number one reason why fish can lose color. Stress is very common among saltwater fish for various reasons and is a critical factor in fish health. Things that cause stress in a fish include overcrowding, handling, unhealthy environment, poor tankmates, and aggressive fish sharing the same tank.

2. Illness or disease

When a fish gets sick, it’s very common for them to lose color. Common diseases include ich, tail and fin rot, swim bladder disease, velvet. All of these items will cause saltwater fish illness and color fading.


3. Poor water conditions

Maintaining proper water conditions is crucial to having a healthy saltwater tank. If your water quality becomes poor, you will have problems keeping healthy livestock. Drastic changes in PH levels, nitrate, ammonia, salt levels, temperature, and other important levels can cause stress in your fish. This stress will cause the fish to lose color very easily.


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4. Improper tank size

It’s important to plan ahead prior to buying your fish and determine the appropriately sized tank you will need. Far too often you will see aquariums that are too small for the fish being kept. Anytime the environment is cramped and there is not adequate space for your fish, stress, and illness will result.


5. Tankmates

Having the proper tankmates living together in the same tank is important for keeping them healthy. Fish that don’t get along will lead to bullying and stress. Bullying can often lead to death but if you planned ahead to have proper tankmates this won’t be an issue. Tankmates that can live together and get along won’t be stressed and will have no trouble maintaining their colors. Use this chart to see if your fish are compatible. 


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6. Aging

Many saltwater aquarium fish do not have long lifespans. Some fish like the Royal Gramma only live for about 5 years. But some fish like the Emperor Angelfish can live 20 years. As these fish age, it is normal to see a loss in color. Sometimes there will only be a slight color change as the age and sometimes it can be more pronounced.


7. Injury

When a fish becomes injured they are subject to illness and disease. Fish can become injured by grazing or flashing against a rock, possible aquarium decorations and rocks falling on them, hurt from wavemakers and other equipment. An injury can lead to heavy stress and the problems that follow including color loss.


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8. New tank adjustment

You can pretty much guarantee when you introduce a new fish to a new tank, there is going to be an adjustment period and the fish may not show it’s full color potential for a period of time. Some fish will adjust faster than others but it’s common for fish to hide for a while and be faded in color until they become more comfortable in their new environment.


9. Lighting change

We know that proper lighting is important for corals to be healthy, but what about fish? Yes, fish can be affected by changes in lighting as well. Fish become accustomed to the lighting that is normally used on your tank. If you make a change to your lighting, you might notice the fish lose their color for a while. Under different lighting conditions, your fishes’ color can change and look different.


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10. Improper diet

I can’t stress enough how important diet is for your saltwater fish. Feeding improper foods can lead to a variety of health issues with the fish. Not all fish eat the same foods. Some fish require a meaty diet and others need a varied diet including herbivores. There are a variety of good quality foods on the market from flakes and pellets to frozen and live foods. There are always plenty of options for you to choose from. Keeping your fish on the right diet will keep them healthy and colorful.



What to do if your fish is losing its color


It is important to check if your fish are suffering from diseases or illnesses which may be contributing to the loss of color. Many treatment options are available and you want to diagnose the illness properly to ensure the right treatment.

If you notice your fish are stressed, there are a few things you can do. First, determine the reason for the stress. Is it a water quality issue? If you checked your water parameters through testing and notice your nitrate levels are too high, a water change is easy to do. Water changes can be a huge help when fish are sick or showing signs of disease.

You may want to remove the fish if showing signs of stress or disease to a quarantine tank for treatment.

Make sure that your fish are in the appropriate sized tank and tankmates are chosen wisely.

Perform regular maintenance tasks to ensure your water quality is suitable. Create a checklist and a schedule to stay on top of the required maintenance items.