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Why Do Betta Fish Jump Out of Their Tanks? 4 Reasons & Solutions

Lindsey Stanton Profile Picture

By Lindsey Stanton

betta fish in aquarium

If you own a Betta fish and were surprised to find that it has jumped out of the cage, the good news is that these fish are quite hardy, and as long as you caught it quickly, it should be ok. We recommend covering the aquarium immediately. However, there are many reasons why your Betta fish might be jumping out of the tank. Keep reading while we list as many reasons as possible for your fish’s behavior and what you might do to fix it to make sure your fish isn’t sick, and no water hazard could lead to other problems.

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The 4 Reasons Your Beta Might Jump Out Of The Tank

1. Ammonia Build Up

Ammonia is toxic to fish, including your beta, and can permanently damage the gill structures and other soft parts of the fish, and some believe it can cause a burning sensation to the fish, which might be causing your Betta to attempt to jump out of the water. Other symptoms to look out for are lethargy, loss of appetite, gasping at the surface, inflamed eyes, and erratic swimming. Your Betta fish will likely try anything to escape the ammonia, including jumping out of the tank.

holding PH tests in front of freshwater aquarium
Image Credit: M-Production, Shutterstock

What Can I Do About It?

As things break down in your aquarium, it creates ammonia. Everything from dead leaves to your Bettas feces breaks down, so there will be ammonia in every tank. The best way to prevent damage to your fish is to test your water frequently with a test strip so you can catch increasing levels before they get out of hand. In our experience, not changing the water frequently enough is the most common cause of an ammonia spike in a tank that’s been running longer than 12 weeks, followed closely by allowing dead plants to remain in the tank too long. We recommend changing at least 50% of the water and using an aquarium vacuum to remove debris on the floor as soon as your test strips indicate ammonia levels are rising.

We recommend allowing your tank to operate without fish for several weeks to allow healthy bacteria cultures to form in the tank that will help control the ammonia. Many inexperienced owners add the fish immediately, which can cause a spike in ammonia as the waste breaks down. This ammonia spike causes many fish to die in the first few weeks.

2. Not Enough Space

group of female betta fish in tank
Image Credit: Hobi Atok, Shutterstock

Keeping a Betta fish is a popular trend, and it creates an attractive moving decoration. It’s possible because the Betta fish doesn’t use gills like most fish do and instead takes small gulps of air from the surface. Breathing air allows the fish to live in stagnant water with very little oxygen. However, just because the fish can survive in a small amount of water doesn’t mean it’s happy about it, and if your fish gets the desire to swim, it may try to leap out of the water.

What Can I Do About It?

While some experts recommend as little as ¼ gallon, many others suggest a much more reasonable five or ten-gallon tank. This space will allow your fish much more room to swim, and we recommend plenty of vegetation your pet can use as hiding spaces.

3. Improper Lighting

dwarf pufferfish in aquarium
Image Credit: Toxotes Hun-Gabor Horvath, Shutterstock

Another reason your fish might try to jump out of the water is that the lighting is wrong. Keeping the lights on all the time can increase anxiety causing the urge to escape.

What Can I Do About It?

Your pet needs to have a regular day and night cycle where the lights are on or off at specified times each day. These day-night cycles allow your pet to get the rest it needs and will allow it to behave naturally. Some owners use a timer to make sure the lighting stays consistent.

4. It’s Just Breathing

Obviously, this isn’t true if you found your fish on the floor, but many inexperienced owners see the Betta racing up to the surface repeatedly, and it could certainly look like your fish is getting ready for a big jump. However, as we mentioned earlier, Betta fish need to breathe air from the surface, and there is a good chance your fish is just getting a breath of fresh air and has no intentions of leaving its happy home.

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If you see your Betta fish swimming to the top of the tank every few minutes, there is a good chance it’s just taking a breath, but it’s darting around the tank like its tails on fire for a prolonged period it could be an ammonia spike. We recommend checking the water frequently and making adjustments before the ammonia levels get too high. Usually, you will only need to change the water and vacuum the bottom when the numbers increase to keep your fish healthy and happy. Always allow a fresh aquarium to run for several weeks before adding your first fish, and you will need to watch for spikes any time you add something new to the tank.

We hope you have enjoyed reading over this guide, and it has helped answer your questions. If you have learned something new, please share our look into why Betta fish jump out of their tanks on Facebook and Twitter.

Featured Image Credit: yin8003211, Pixabay

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