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How Long Can a Goldfish Go Without Eating? What You Need To Know!

Goldfish filter

Goldfish are hardy and adaptable fish and can go for up to 2 weeks without eating. However, just because they can go for a long period without eating, it does not mean that is recommended to not feed your goldfish for extended periods of time.

Feeding your goldfish the right foods on a regular feeding schedule is important for their health and vitality. Goldfish need food as fuel to be able to swim and go about their daily activities normally.

If you are wondering if you can leave your goldfish without food while you are on vacation or if you are merely curious as to how long goldfish can survive without being fed, then this article has all the answers for you!


How Long Can Goldfish Go Without Food?

The exact duration of how long a goldfish can survive without eating depends on the current state of your goldfish’s health. If the goldfish is already malnourished and being fed an improper diet, then they have a shorter period of survival if they are deprived of food. A healthy goldfish can go for approximately 1–2 weeks without food before they start to become ill or die.

In the wild, goldfish will often go a few days without eating since they are grazers and eat whatever food is available for them. Their situation in captivity is different, though, as owners will usually feed our goldfish every day. Feeding your goldfish a variety of different foods each day is recommended so that you can ensure they are getting enough nutrition.

If your goldfish are not being fed, they will begin to forage for food amongst the substrate to find any morsels of food leftover from previous feedings. If you have a planted aquarium, you might notice that your goldfish will begin to eat your live plants because they are hungry.

In more severe stages where a goldfish has not been fed for a while, you will notice that they have a humpback appearance, this is because they are losing weight rapidly and their spines will start to stick out. This can affect their quality of life and energy levels, which is why it is important to ensure your goldfish do not go for more than 3–4 days without a decent meal.

Many goldfish die as a result of improper feeding, diet, and/or portion sizes – which can be easily prevented by proper education.

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Should You Fast Goldfish?

Goldfish tank with gravel substrate
Image Credit: Hineck, Pixabay

Fasting is a common practice amongst goldfish keepers because it is believed that by doing this your goldfish will have a lesser chance of developing the buoyancy problem known as swim bladder disorder (SBD). This theory has not been scientifically proven as an effective method to fix or prevent swim bladder problems from occurring, though. The main belief stems from goldfish overeating (especially fancy-bodied goldfish that have rounded stomachs) may result in their full bellies pressing on their swim bladder and preventing them from controlling their buoyancy in the water efficiently.

Instead of fasting your goldfish, it may be better to feed your goldfish that have trouble with swim bladder disorders smaller meals throughout the day that contain easily digestible materials.

How Often Should Goldfish Eat?

All breeds of goldfish should eat at least once a day. The amount of food they eat will depend on their size, as larger goldfish typically eat more than small goldfish. Goldfish are omnivores so their diet should include both vegetative matter and animal-based protein.

High-quality pelleted food should be fed as a staple to your goldfish, and their diet can be substituted with other commercial foods such as freeze-dried worms, or you can feed them blanched vegetables a few times a week.

If you happen to be going on vacation or will be unable to feed your goldfish while you are away, they will be fine for up to 3 days, but if you’re away for longer, you should have a trusted friend or family member feed them while you are away. You also have the option of placing a “vacation feeding block” in their aquarium while you are away, but it may cause the water quality to foul quickly.



The key to keeping your goldfish healthy is to ensure that they are being fed a balanced diet rich in the vitamins and other nutrients that they need to remain healthy. Goldfish are intelligent, and their biological clock seems to tell them exactly when feeding time is, which you may notice by their excitement and gasping mouths near the area where you frequently feed them.

You should stick to feeding your goldfish regularly and not purposefully deprive them of food, as it may do more harm than good.

Featured Image Credit: Zinaida Zakharova, Shutterstock

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