10 Reasons Why Betta Fish Hide (& What Can You Do About It?)

Hiding should generally be a short-term behavior. If your betta hides all the time and doesn’t come out, there may be a problem with the tank.

A betta fish might be hiding in the tank because of factors in their environment such as water quality, lights, changes within the tank such as tank mates or water changes, or because the fish themselves are sick, injured, or depressed.

Bettas naturally like to have places to hide in a tank, so monitoring your betta’s behavior will allow you to see if they are hiding more than usual.

Betta | Photo 18765880 © Dmitryon | Dreamstime.com

Why Is My Betta Fish Hiding?

The main reasons a betta fish will hide are:

  • The filter current is too strong.
  • The tank lights are too bright.
  • Poor water quality.
  • Ammonia, nitrite, and nitrate levels too high.
  • The betta is injured, sick, or depressed.
  • The betta is new to the tank.
  • New or incompatible tank mates added.
  • Changes outside the tank.

We will explore each of these reasons in-depth and ways to prevent your betta from hiding.

You Aquarium Makes Them Feel Exposed

There are a number of different things that can make your betta want to hide.

If you have just bought your betta or it has only recently been added to the tank it could be hiding because it doesn’t feel safe in the new environment. This is particularly true if you’ve moved your fish from a small bowl into a large tank.

Bettas are preyed upon in the wild by both birds and larger fish, so they try and find somewhere they can hide away that allows them to feel safe in their new tank. Adding plants, driftwood, and caves will help them to feel more secure as they can hide away in these places.

Similarly, if you have just purchased or recently added your betta to its new home then it may be suffering from some stress. You need to ensure that the water temperature is correct (warm) and that there are no other fish in the tank with it.

If you have had your betta for some time then check whether anything has changed within its environment that might be stressing it out and making it want to hide. If you have recently added new decor or changed your tank’s layout, they may just need a chance to get used to the new environment.

Strong Filter Current

Bettas come from rice paddies, marshes, ponds, and canals in Thailand and the surrounding areas, so they are used to still or very slow moving water.

They have been bred to have long fins and so are not naturally strong swimmers, so if the filter current is too strong the betta will hide to avoid being blown around.

You can alter the flow rate on the filter, angle the flow away from the fish, add holes to the output hose, or cover the filter with a filter sponge to slow down the current.

Bright Lights

Bettas are shy by nature and prefer subdued light levels in their tank. If you have bright lights in your tank it might be too bright for your betta’s comfort level and he might feel more comfortable hiding behind plants or objects in your tank where it’s darker.

Try either using dimmer lights or reducing your lighting to 3-4 hours per day max, especially if you have algae issues in the tank (less light will = less algae).

If all else fails, putting a floating plastic plant or floating living plants in your tank can provide your betta with lower light levels in the tank and places to hide (among the roots of living plants) as well.

Bettas live in murky water with lots of plants in the wild, so this will also help reproduce their natural environment a bit and make them feel more comfortable in their tank.

In short, turn the lights off in your tank, get dimmer lights, or cover up to half of the tank with floating plants so they can breathe in air but there is shade at the bottom of the tank.

Your Water is Too Cold

If they are hiding by the heater unit, they may be too cold. Some of the signs that a betta is too cold are:

Lethargy – if your betta has become lethargic and sits at the bottom of the tank not moving, he may just be cold.

Clamped fins – if his fins are clamped tightly to his body, this can be a sign that he is too cold.

He doesn’t eat – in colder temperatures, bettas metabolism will slow down, resulting in them eating less.

Hiding by the heater or filter – if your betta is hiding by either of these two items, it might indicate he is seeking out warmer areas in the tank.

Carry out a water change and ensure the temperature is between 75- and 80-degrees Fahrenheit. Don’t change more than 50% of the water in the aquarium at once as if the water is changed too quickly this can shock them and they will hide.

Ammonia, Nitrite, and Nitrate Levels Are Too High

If bettas are hiding by the filter, it might be because the water here is cleaner than the rest of the tank.

Test the water parameters with a water test kit. If the ammonia or nitrate levels are too high it can damage your betta’s gills, making it difficult for your betta to breathe.

Betta are much more resilient to poor water quality than other fish, since they have a labyrinth organ that lets them breathe air from the surface, but it’s still a good idea to keep their water clean.

This will keep them healthy and reduce the chances that they will go into hiding because of the poor water quality in your aquarium.

New In the Tank

As I mentioned above, if a betta is new to a tank, they often hide at first until they feel safe and comfortable. If a betta is new to a tank, they often hide at first until they feel safe and comfortable.

You must give them time to adjust to their new surroundings. This can take anywhere from a few days to several weeks. A good rule of thumb is the bigger the tank the longer it will take for your betta to adjust and start exploring their environment.

Your Betta is Injured or Sick

If a betta is injured or sick, they will hide as they are feeling vulnerable and not wanting to show they are hurt, due to fears of being preyed upon in the wild.

Common illnesses can be bacterial infections, fungal infections, or parasites. Check your betta for any signs of these, including ragged looking fins, white spots appearing on their body, or your betta having trouble swimming normally.

These illnesses can usually be treated with medication which you add into the water. Some medications require you to do a water change before and after treatment. The days of treatment are also important so if you think this might be the issue do some research on what is wrong with your betta to make sure you do the treatment correctly.

Your Betta is Bored and/or Depressed

It’s a little known fact that betta fish can get bored in their tanks. If you own a betta, it’s important to ensure you’re doing everything you can to help them stay happy and healthy.

Betta fish, like most animals and humans, need to be stimulated in order to prevent boredom. Betta are very intelligent and can become depressed if they are not stimulated.

This can lead to lethargy and hiding.

If your betta has a large enough aquarium with plenty of plants, caves, or other decor he or she can swim through and hide in, it’s much less likely they’ll be bored.

You should also make sure the tank is big enough for them to swim and explore. (A 5 gallon tank or larger is best.)

Your Betta’s Tank Mates Are Making It Feel Nervous

Bettas are territorial and if new tank mates have been added that the betta feels are threats, it may hide or act aggressively (or both).

If you’ve introduced new fish into the tank, check to see if your betta has been bullied or attacked by them. If he’s been nipped at by other fish while in the tank with them, he’ll be wary of leaving his hiding place and will probably stay there until the aggressor is removed from the tank.

Check which fish make good tank mates for bettas and how much space each fish needs. I have guides on the best tank mates for bettas in 5 gallon and 10 gallon aquariums. Smaller than that and it’s not a good idea to keep anything else in the tank with your betta.

Changes Outside the Tank

Bettas can be sensitive to vibrations and can be scared by loud noises.

If you have placed something near to the tank that wasn’t there before such as a TV or sound system, the vibrations might be scaring the betta and causing them to hide.

If your betta is scared of noises, try turning off any loud appliances/TVs in your home and see if he comes out of hiding.

If this works, you may want to move your betta’s tank to somewhere else.