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Why Is My Goldfish Not Eating? 7 Vet Reviewed Reason

Are you worried about why your goldfish isn’t eating? Don’t panic! There are seven vet-reviewed reasons why it might not be eating, and it’s important to understand the cause so you can help your fish.

In this article, we’ll look at water quality, temperature, stress, diet, tank mates, disease and aging to find out what’s behind your goldfish’s lack of appetite.

Key Takeaways

  • Poor water quality and overfeeding can affect the appetite of goldfish
  • Maintaining the right temperature and creating a calm environment reduces stress and promotes healthy eating habits
  • Proper nutrition and a variety of foods in small amounts keep goldfish interested in eating
  • Tank mates and social interaction can encourage eating habits, but overcrowding should be avoided

Water Quality

Poor water quality can cause your goldfish to stop eating. High pollution levels in the aquarium or tank can lead to a decrease in oxygen, making it difficult for your fish to feed properly.

The right amount of food is also essential, as overfeeding can cause health issues that may affect their feeding habits.

Ensuring the water is clean and maintaining a healthy diet will help keep your goldfish active and full of energy.


Maintaining the right temperature for your goldfish is important for their health and wellbeing. Water temperatures should ideally stay between 65-75 degrees Fahrenheit. The tank should be kept at a temperature that doesn’t fluctuate drastically. Too high or too low temperatures can cause stress in your fish. It’s important to monitor both water and tank temps regularly.

Water Temp

Checking the water temperature in your goldfish’s tank is key. If it’s too cold or hot, they might not eat. A parasite infestation or diet changes could also be causing a lack of appetite.

To ensure your fish is comfortable, keep the temp between 68-72°F. Consider adding a thermometer to monitor temps and avoid any issues with your pet’s eating habits.

Tank Temp

Keeping your tank’s temperature in the optimal range of 68-72°F is essential for your fish’s health and happiness. Not only does it affect their feeding habits, but also their overall wellbeing.

Tank size also plays a role; larger tanks are better able to maintain stable temperatures.

To ensure your fish stay healthy and happy, make sure you keep their tank at the right temp!


Stress can cause your goldfish to stop eating, so it’s important to make sure their environment is peaceful. Proper lighting level and water chemistry are essential for a stress-free tank.

Goldfish can become stressed if they feel too crowded or overstimulated by bright lights, noise, and activity around the tank. Stressful situations can lead to physical symptoms like loss of appetite and fin damage in fish.

Creating a calm atmosphere with fewer distractions can help reduce stress on your goldfish and encourage them to start eating again.


Making sure your goldfish get the proper diet is essential for their health and well-being. Poor nutrition or stale food can cause them to stop eating, which has long-term consequences.

Consider providing a variety of foods in small amounts, as this will help keep them interested. A balanced blend of flakes, pellets, or freeze-dried food is ideal and should be rotated on a regular basis to prevent boredom.

Regular water changes are also necessary because goldfish produce lots of waste that affects water quality.

Serve your fish with care to ensure they stay healthy and happy!

Tank Mates

Continuing with the discussion of why your goldfish isn’t eating, another factor to consider is its tank mates. Goldfish are naturally social creatures and may not be getting enough interactive play if they’re alone in their tank.

Additionally, overcrowding can lead to stress and illness. Therefore, it’s important that you have an appropriate number of fish for your tank size.

If your goldfish has a buddy or two, it might just give them the boost they need to get back on track with their diet!


If disease is a factor, it’s important to take your fish to the vet for a review. Disease can be caused by a variety of social and environmental factors, such as overcrowding, improper diet or water quality changes.

Ensure that all tank mates are compatible in size and temperament so that your fish don’t fight or become ill. Monitor the water chemistry regularly and provide them with plenty of clean oxygenated water to help keep their systems healthy.

Take note of any changes in behavior or appetite as they could be signs of illness. If you suspect any type of disease, visit the vet promptly for advice on how to treat it accordingly.


As your fish age, they’ll require more specialized care.

Aging signs in goldfish can include changes in behavior, appearance, and diet. Some new eating habits may seem harmless at first, but a steady decline in appetite could be a sign of aging.

To ensure your fish’s health, you should monitor changes in diet and adjust accordingly. Many owners find that offering smaller meals more frequently can help keep their older fish well-fed and healthy.

As your fish ages, keep an eye out for any dietary changes that may need to be addressed with specialized care.

Frequently Asked Questions

How Often Should I Feed My Goldfish?

Feed your goldfish proper portions of fish nutrition each day. Ensure that it is not overfed as this can cause health problems and prevent them from eating properly.

What Type of Food Is Best for Goldfish?

Feed your goldfish a varied diet and keep the water temperature consistent to maintain a healthy lifestyle. Offer high-quality food, such as flakes or pellets, that are designed specifically for goldfish. Supplement their meals with live foods like brine shrimp or bloodworms occasionally.

How Do I Know if My Goldfish Is Sick?

If your goldfish has stopped eating, it may be a sign of illness. Look for changes in behavior such as swimming slower or staying near the bottom of the tank. Check the water temperature and make sure the environment isn’t too stressful. If you notice any of these signs, seek help from a vet to ensure your fish’s health.

How Often Should I Change My Goldfish’s Water?

You should change your goldfish’s water at least once a week to maintain the optimal temperature and filter maintenance. Monitor the water condition regularly, as goldfish can be sensitive to changes in their environment.

How Big Should My Goldfish’s Tank Be?

The size of your goldfish’s tank should depend on the number of fish and their size. Generally, you’ll need at least 10 gallons per fish, plus additional space for filtration and to ensure proper water temperature.


It’s always concerning when your goldfish stops eating. Thankfully, there are a few common culprits that you can easily investigate. These include water quality, temperature, stress, diet, and tank mates. Disease and aging may also be factors to consider if the issue persists.

Remember to take your time when troubleshooting. With patience and care, you’ll be able to get your fish back on track!



Meet me, your dedicated author and fish aficionado. With a deep-rooted passion for all things aquatic, I bring a wealth of knowledge, experience, and enthusiasm to this fish and aquarium website. As an avid fishkeeper myself, I understand the joys and challenges that come with creating a thriving underwater world. Through my articles, guides, and recommendations, I strive to provide you with accurate, reliable, and engaging content that will enhance your fishkeeping journey. Join me as we dive into the fascinating realm of fish and aquariums, and together, let's make your aquatic dreams a reality.

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