Why Won’t My Betta Fish Eat? – 6 Possible Reasons Why

Why Won't My Betta Fish Eat

Betta fish or Siamese Fighting Fish are a popular choice for many people. They’re beautiful, intelligent, and most importantly, they require very little space! But why won’t my betta fish eat? There can be several reasons why your betta fish may not want to eat what you offer it.

I have compiled this list of 6 main reasons why your betta might not want to eat:

1) Stress

2) Diet

3) Lighting in the tank

4) New Tank Syndrome

5) Sickness or Disease

6) Environment

Betta fish are very intelligent and very sensitive to stress. This is a common reason betta fish stop eating. If you think your betta is stressed, be sure to provide a secure space for it and try not to handle it too often or make loud noises around its tank, as this will stress them out even more!

Because your betta cannot tell you what is wrong, figuring this out will be a matter of trial and error.

Throughout this post, we will briefly look at each of the 6 main reasons listed above that may impact why your betta fish is not eating.

Make sure to check out our Betta Fish Care Guide And Species Overview.

Is Your Betta Fish Not Eating Due To Stress

Stress plays a major factor when fish behavior changes from the norm. Fish often get stressed when they are moved to a new tank or an increase in activity around their environment.

Stress can also be caused by aggressive fish living nearby and even by loud noises (like the sound of your hairdryer). If you notice stress symptoms like fins clamped together with no movement, your betta fish may not eat for this reason.

Is Your Betta’s Diet Affecting Them

Betta fish need to be fed a balanced diet to stay healthy. Bettas are carnivorous fish but will eat a varied diet, including plant matter (such as leafy vegetables) and animal meat/protein.

betta fish jumping for food
Betta fish jumping for food.

A bettas diet should consist of around 80% sinking pellets and 20% freeze-dried foods such as freeze-dried bloodworms or brine shrimp once or twice per day for adults, typically in the morning and evening after lights out since betta fish often are more active at this time.

Betta fish are picky eaters. If you are not feeding your betta fish the right type of food, it may starve and stress out even more! Be sure to research what types of food betta fish eat to keep them healthy and happy.

A betta’s eating habits can vary, and a change in diet can cause a betta fish to stop eating from time to time, so you must provide the right type of food at all times! If your betta is a picky eater and there is less variety available, it will be more likely to starve itself.

Ensure that you provide enough live and varied foods that your betta fish will want to eat. It may be obvious to some, but simply switching to a new food may cause your betta to begin eating again.

Best Foods For Betta fish

The best live food for betta fish are:

  • Bloodworms
  • Blackworms
  • Mosquito larvae (no more than one per week)
  • Frozen brine shrimp and daphnia
  • Cut up pieces of earthworm or nightcrawler

The best freeze-dried food or frozen foods for betta fish are:

  • Frozen bloodworms
  • Frozen brine shrimp
  • Dried bloodworms
  • Earthworms (dusted with vitamin and calcium powder)

All of the above betta food should be available at your local pet store or fish store, although live foods are sometimes more difficult to come by.

Betta pellets are also a staple food; make sure you always buy high-quality food as cheap food may be putting your betta fish off eating.

Trying a variety of different foods may be all that it takes to get your betta fish to start eating food again, as they may just be holding out for some better food!

One final consideration is, are you giving your betta too much food? Your betta may be too full to eat food.

Poor Quality Tank Lighting Can Stress Your Betta

If you are providing the best possible food, but your bettas still lack appetite from time to time, it’s also important that you look at your lighting situation in the tank! Lighting can have an effect on both stress and diet for many reasons (including seasonality).

All living things need light to survive, but bettas require a special kind of lighting. Betta fish require a light that emits blue and red wavelengths to thrive.

The betta fish needs blue light to stimulate appetite and digestion and red light to carry out necessary biological functions.

If your betta fish does not get the right type of light, it may stress them out and cause them to stop eating.

Betta Tank LED Lighting
LED Fish Tank Light Housing

Try using a low-wattage LED tank light or even just an energy-efficient bulb at night, which should be dimmed so that it emits red wavelengths only during this time of day. For best results, you can purchase specific lights made for betta fish, whose needs are different from other fish.

Can New Tank Syndrome Cause My Betta To Stop Eating

New tank syndrome occurs when a new environment does not have the correct water parameters for your betta fish. You may be doing a great job of caring for your betta, but if the tank conditions are not right, why would they want to eat?

If you have a new betta fish, the stress of a new tank may cause your betta to stop eating. You will need to wait at least two weeks before adding fish and plants into the tank to stabilize the water parameters. However, sometimes it takes longer than this for all factors in your aquarium environment (such as temperature) to be stable enough for any living thing to thrive.

Is it a community tank with other fish in the same tank? Are the other aquarium fish eating well?

Is Your Betta Sick (A Symptom Is Not Eating)

Like many other species of tropical freshwater fish, Betta fishes can become sick even with regular water changes. If you notice any of the following symptoms, your betta fish may be sick and not eating:

  • Difficulty swimming or staying upright (Swim bladder disease)
  • Not being as active as it usually is
  • Cloudy eyes, fins clamped together with no movement, discoloration in color (usually white)
  • Sunken eyes or abdomen, scales sticking out more than usual
  • Betta fish get diseases easily, and stress is also a cause of lowered immunity to disease. If you notice any of these symptoms, then your betta may be unwell!

If a betta is showing signs of illness and it is not clear about the cause, the stress of being sick may cause your betta to stop eating.

Ensure that you quarantine any new fish (even if they are from your own tank) so that there is no cross-contamination in a shared tank and provide your betta with suitable food as outlined above.

You may notice other symptoms that I have not mentioned. If your betta is still not eating, you may need to take them to the vet as there could be another underlying problem.

Is Your Betta’s environment At Its Optimum

The environment in which a betta fish lives is also crucial for your betta fish, and if it is not at its optimum, your betta fish won’t eat!

You must provide an aquarium with suitable filtration to help avoid poor water quality.

As betta are tropical fish, the water temperature should ideally resemble a tropical climate, in the range of (78-82°F/26-28°C).

aquarium water test kits
Use a test kit to regularly test your fish tank water parameters

Cold water can slow your betta’s metabolism where they will burn fewer calories and not require food as often. I talk about this in another article that you can read here: How Long Can Betta Fish Go Without Food (Before getting ill).

Water temperatures are important but the other aquarium water parameters will also need to be checked because spikes in ammonia and nitrates can cause fish to feel unwell and lethargic.

Does your aquarium water look dirty? If you have dirty water, a simple water change may help make your betta feel better.

Frequent water changes are good, but don’t change your tank water too often, and don’t remove too much of the water, as you will remove much of the beneficial bacteria, which help to break down waste and remove ammonia from your tank. Also, make sure to add a water conditioner when carrying out a water change to avoid chemicals such as chlorine from entering the tank.

It would be best to always keep your betta tank similar to a bettas natural environment where they will feel most relaxed. You can do this by adding live plants, ornaments, and the correct substrates such as gravel, sand, or clay.

Is the external environment stress-free? Betta fish can hear noises outside of their tank, and loud noises can cause your betta to feel frightened or stressed. If you are interested in finding out more about a betta’s ability to hear, why not read my article Do Betta Fish Like Music? You’re About to Find Out!

Many betta owners report that they will form bubble nests when their betta fish are happy in their environment. A bubble nest is where a betta will blow bubbles at the surface that form a nest of bubbles. This is a natural breeding behavior and is usually found in male betta fish, who in the wild will make their nest under leaves while waiting for a female betta.

Bubble nests are a good sign of a healthy and relaxed betta fish, but if your betta does not make a bubble nest, it is not necessarily a bad sign either. Not all bettas exhibit this behavior.


It can be hard to tell why your betta fish is not eating. For example, you may notice that your betta stops eating when you are at work, but it’s tough to know why! Stress is probably the reason if you have considered all these things and still cannot find out why your betta is not eating.

Betta fishes do stop eating from time to time, and there isn’t one single cause. Hopefully, my list of possible reasons why your betta is not eating will help you discover why and resolve it.

Frequently Asked Questions

Jon O'Connell

I have kept both marine and freshwater fish and set up almost 100 aquariums. Happy to share my knowledge and experience to help others enjoy keeping healthy and happy fish.

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