Betta Fish Not Eating – Everything You Need To Know And How To Fix It

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Welcoming a new betta to your home is always an exciting affair. But if you’re a first-time fishkeeper, you may notice some behavioral changes in your betta over time. Some of these changes are perfectly harmless, but appetite loss is often a sign that something is wrong.

This detailed guide covers some of the most common reasons why your betta may not be eating. We’ll also discuss how you can fix these issues, and prevent them from recurring in the future. Without further ado, let’s dive right in!

Why Is Your Betta Fish Not Eating?

Disease and Illnesses

Think about the last time you were sick. You may have felt sluggish, tired, and had no appetite. The same can happen to your betta. If your betta hasn’t been eating lately, be sure to rule out any common diseases. These may include ammonia poisoning, bacterial infections, fungal disease, or swim bladder infections. This list is by no means exhaustive, so be sure to pay close attention to any signs of disease.

Because appetite loss is such a common symptom in sick betta fish, it is important to have your fish checked out by a veterinarian if you suspect any disease or illnesses. Look for behavioral changes, physical changes, or any signs of an infection – it’s usually pretty easy to tell the difference between a healthy betta and a sick one.

The Solution


If your betta is indeed sick, you can do one of two things. First, you can take your betta to a veterinarian who can diagnose the illness and provide specific treatments. Generally, you would do this if you need some additional help with the diagnosis – which we highly recommend if your betta is not eating or showing any other symptoms of illness.

Second, you can opt for commercially available medications specifically designed to treat common betta diseases. However, you should only administer medications after you have a good idea of what is causing the illness. Trust us – using the wrong type of illness causes more harm than good, and you do not want to take chances with a fish that is already feeling under the weather.

After addressing the underlying illness, your betta should regain its appetite. Your fish may not get back to 100% immediately (who does after being ill?), but it should soon return to its regular eating habits. If your betta still doesn’t seem to be eating, it could mean that there’s another factor contributing to its appetite loss. Let’s move on to the other possible factors.

Poor Water Quality

Bettas also lose their appetites when they are kept in poor water conditions. Fish that live in dirty water are placed under chronic stress due to the toxic levels of ammonia, nitrite, and nitrate present. They are also more likely to fall ill, have a weaker immune system, or even die. Despite the betta’s reputation for being a hardy fish, they should not be subjected to tank conditions that are unhygienic or even dangerous.

Sometimes, poor water quality can be caused by a subpar source. For instance, if you’re using tap water, you need to test it to ensure that it doesn’t contain harmful chemicals. And if you’re using groundwater from a well, you need to make sure that the water is clean and purified before using it in your tank. We highly recommend investing in liquid test kits that will get the job done for you.

dirty aquarium

Next to illnesses, poor water quality is the most common culprit behind bettas that suddenly decide to stop eating. So if you suspect this might be the case, please do something about it!

The Solution

The first thing you should do is ensure that there’s enough water, to begin with. Bettas need at least 5 gallons of water to be healthy and comfortable. Having more water also prevents toxins from building up as quickly. Additionally, it’s important to keep up with regular water changes, as this will help ensure the water quality remains good. We recommend changing out about 25-50% of the water once per week.

If you haven’t already, you should also invest in a good quality water filter. Please look for something that is specifically designed for betta tanks. These filters will usually have an adjustable filter flow to accommodate the betta’s need for gentle currents. At the same time, they should work effectively to keep the water clean and free of toxins.

Finally, you should be sure to keep the tank clean by removing uneaten food and waste. Personally, I like using a turkey baster to siphon out small bits of uneaten food and other debris. I find that doing this every other day is usually enough to keep the tank clean. You can also opt for a gravel vacuum, of course. Since the latter is a bit more involved, you can shoot for weekly sessions instead.

Inappropriate Water Parameters

Water parameters are tangentially related to water quality, but they aren’t quite the same thing. When we talk about maintaining ideal water parameters, we are usually referring to things like water chemistry and water temperatures. And yes, inappropriate water parameters are yet another common reason why bettas lose their appetites.

water ph tester

One of the most common mistakes made along these lines is keeping bettas in cold water. Okay, “cold” may be subjective, but bettas have a very specific temperature range that they are most comfortable in. The ideal temperature for these tropical fish lies between 76 to 85 degrees Fahrenheit, and you will also need to keep the temperature constant. This means no fluctuations, even if it’s only a few degrees.

Another common mistake is keeping your bettas in water that is too hard. Though these fish are tolerant of a wide hardness range, keeping them in hard water for extended periods of time will eventually take a toll on their health. If your betta’s water has a hardness of above 25 dH, please consider taking steps to soften it.

The Solution

Maintaining an ideal tank temperature is easy – you simply need to invest in a reliable aquarium heater. Most models are fairly inexpensive and relatively easy to install. Be sure to choose a heater that is suitable for your tank size, and always read the instructions carefully. A thermometer also comes in handy, because you want to make sure that the heater is doing its job.

When it comes to water hardness, you can use a variety of products, such as water conditioners, to soften the water. If you want to go the natural route, you can also use Indian almond leaves to soften the water. Whatever you decide to do, make sure that you don’t make any sudden changes. Any changes to the water chemistry should be done gradually, so that your betta has time to adjust.

Because these adjustments need to be gradual, you may not notice a dramatic improvement in your betta’s appetite right away. But if you stick to it and maintain the ideal water parameters, you should eventually see an improvement. It is also a good idea to research a betta’s specific needs before committing to raising it as a pet.

Unmet Nutritional Requirements

Bettas have a reputation for being a bit of a picky eater, but this isn’t an excuse to feed them a poor diet. Many people make the mistake of opting for general-purpose fish flakes. Unfortunately, these flakes are usually formulated for omnivores. While your carnivorous bettas may eat these flakes due to a lack of alternatives, they will not get their needs met. This eventually leads to a general lack of appetite.

In some cases, your bettas may lose interest in their food, even if you’ve opted for pellets that are formulated for bettas. This can be frustrating, but sometimes, even betta pellets may not provide your fish with everything they need. These fish usually need a protein boost in the form of freeze-dried or frozen food. Even carnivores need a varied diet consisting of multiple protein sources!

The Solution

Naturally, you should always provide your betta with a high-quality betta pellet as their staple diet. However, you should also supplement this with a variety of other foods. This could include frozen bloodworms, brine shrimp, and even freeze-dried krill. In the wild, these fish feast on mosquito larvae, so please don’t be afraid to give them a little bit of variety. Just make sure to do your research first!

One possible setback is that you may not always be able to find the best food for bettas in your local pet store. Fortunately, there are plenty of reliable websites that offer great quality food at a reasonable price. You could also raise your own food, such as brine shrimp, which is relatively simple and cost-effective. This gives you a ready supply of food that you know is fresh and of the highest quality.

Given the many types of food that bettas need in order to stay healthy, it is important to ensure that you provide a wide variety of options. This way, you can make sure that your fish are getting the nutrition they need to stay happy and healthy. Even the pickiest of bettas will have trouble resisting the allure of a juicy, fresh bloodworm or a yummy little pellet that was formulated with love!

Abrupt Environmental Change

Believe it or not, your bettas may lose their appetite if they’ve been overexposed to a sudden environmental change. These changes may be related to water parameters, or they could be something as simple as the addition of a new filter or decor. Bettas take time to adjust to new environments, so if there’s a sudden change, your betta may not feel comfortable enough to eat.

Even if these environmental changes aren’t inherently harmful or dangerous, they can still stress out your betta. For instance, upgrading your tank filter may seem like a good thing, but if your betta isn’t used to the new position of the filter or the new water movement, it may become scared and refuse to eat.

Of course, we also have abrupt environmental changes that are inherently dangerous to bettas. These include sudden temperature changes, drastic pH shifts, or even the addition of a new, aggressive tankmate. Obviously, these are big no-nos, but many people who make these mistakes don’t realize the consequences until it’s too late.

The Solution

adding water

The best way to prevent your betta from going off their food due to abrupt environmental change is to introduce changes slowly and gradually. If you’re making a major upgrade, such as adding a new filter, start running it at the lowest water flow setting and gradually increasing the water flow over time. That way, your betta will be able to adjust to the new filter without feeling too overwhelmed.

It’s also important to be mindful of the other environmental changes you make. If you’re adding a new tankmate, wait at least a few days to make sure they get along. If you’re making a big change to the water parameters, such as adding a new substrate or changing the pH, then do it slowly over a period of time.

It can be difficult to predict or determine the specific environmental changes that will trigger your betta’s appetite loss. Still, if you remember to introduce changes gradually and carefully, you should be able to avoid this problem.


Last but not least, we have overfeeding. This common mistake may cause your betta to turn down food. And in our opinion, this is perfectly natural. Think about the last time you stuffed yourself with one too many spring rolls at the buffet line – you probably didn’t want to eat for the next couple of hours! Your betta friends are wired the exact same way – even if they may act like bottomless pits at times.

Unfortunately, by the time your betta starts rejecting food, they already have too much inside their stomach. This isn’t always life-threatening or dangerous, but in the worst-case scenario, it may lead to constipation, swim bladder disorders, and potentially, death. This is why many betta owners are accused of killing their fish with kindness – overfeeding wreaks havoc on your betta’s digestive system and health.

The Solution

Woman feeding beta fish in aquarium at home.

Always, always feed your bettas in moderation. A good rule of thumb is to feed your fish only as much as they can eat in a minute. Another rule is to feed an eyeball-sized portion of food. If you opt for this method, you want to make sure you soak the food first. Fish flakes and pellets usually expand exponentially once they’re in your fish’s belly, and you want to accommodate that change in size.

You should also stick to a regular feeding schedule. Haphazard feeding can cause you to feed your fish one too many times a day, while regularly-scheduled meals will help you keep your betta’s diet in check. Usually, I like to feed my fish twice a day. I like using an automated fish feeder on busy days – it helps me keep my betta’s diet in check without any extra effort from my end!

If you are especially concerned about overfeeding, you can also try fasting your betta once a week. While there haven’t been any official studies conducted to examine the effects of fasting on bettas, many experienced betta owners swear by it. Fasting your betta for one day every week can help reset your digestive system. It can also make your betta more likely to accept food once the fast is over.

Final Thoughts

We hope this article gave you a comprehensive overview of why bettas stop eating! Many of these issues are easily resolved, so please do not panic if you find yourself in this situation. Just read our guide carefully, and take the proper steps to help your betta.

If you have any questions or comments about why bettas stop eating, please let us know in the comments below. And if you found this article helpful, do share it with a fellow betta enthusiast! Thanks for reading, and happy fishkeeping!

Wanda is a second-generation aquarist from the sunny tropics of Malaysia. She has been helping her father with his freshwater tanks since she was a toddler, and has fallen in love with the hobby ever since. A perpetual nomad, Wanda does her best to integrate fish-keeping with her lifestyle, and has taken care of fish in three different continents. She loves how it provides a nice break from the hustle and bustle of life.

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