Are Betta Fish Happy In A Small Tank? What They Really Need

Are betta fish happy in a small tank?Are your betta fish going to live a long and happy life in a small tank? The answer is no they are not happy, and they will eventually get sick and die because of the poor habitat.

A little too harsh? Good!

Many fish stores sell betta fish in smaller tanks. This is for practical and economic reasons, not because it’s great for the fish. Male fish cannot live with other bettas on a regular basis, so in order to get the most fish on the shelves, stores have to place them in separate small containers.

If they placed them in a big tank, the male betta fish would all fight and there wouldn’t be any product left to sell.

When people think of betta fish, they often imagine them in a glass bowl with some kind of funky live plant. Often these beautifully colored fish are seen as decorations and centerpieces rather than pets. This is not beneficial to the fish in any way.

There are many things to keep in mind when purchasing a tank for your betta fish. Here are five things you have to think about.

What Size Of Tank Does My Betta Need?

Betta fish are just like other fish, they need the room to swim around and enjoy their home. It’s recommended that the minimum tank size for one betta fish is 5 gallons. Keep in mind that everything you put inside the tank will also affect the amount of water you can put in the tank.

So if you have a regular 5-gallon tank, there will be less than 5 gallons of water if you cram the tank full of decorations.

Also, remember that you’ll possibly need a filtration system or oxygenation system of some kind. If your tank is filled to the edge and you add an oxygen pump, you might have a bit of a mess on your hands. Any tank you get still needs to have a bit of room at the top.

Betta fish are extremely active fish, that’s why they need space to swim around. If they can’t do that, they will become lethargic over time. In this article, we show you how an active betta should behave and how to detect lethargy in betta fish – you should never buy a lethargic betta.

If you have more than one betta, you’re going to want to get a bigger tank. You don’t necessarily need to double the size if you have two, but you certainly need to add a couple of gallons. The fish will all want their own space.

The typical ratio is 2:1 of gallons per inch of fish. Bettas can get up to three inches in length. If you have two of similar size in the same tank, you’ll want twelve gallons of water.

 The Sex Of Your Beta Fish

Male betta fish are very territorial and aggressive toward other male bettas. They cannot be placed into the same tank or they will fight. Even if you put them in tanks right next to each other they will start acting up.

Flaring (when they flash out their beards) will occur and that means the fish are about to get down to business. The video below shows how that looks.

Females can live together, but they shouldn’t live with males. Breeding bettas is a tricky task because male fish cannot easily cohabitate with others of its own kind.

If you plan to have females in the tank, remember they can get mean, too. Especially if there’s only two. They’ll definitely get on each other’s nerves. Experts recommend keeping at least five females, known as a sorority, so this will have an impact on how large of a tank you get as well.

How To Tell The Difference Between Males And Females

When trying to figure out the sex of your betta you need to be looking at grown, mature fish. Looking at fry that aren’t fully grown will mean you aren’t necessarily seeing all of the indicators of the sex.


  • Will be more vibrant and colorful;
  • Have much longer fins;
  • Have bigger beards;
  • Look at you straight on when they are flaring;
  • Longer and thinner than females; and
  • Make bubble nests when ready to mate.


  • Usually less colorful than males;
  • Have shorter fins than males;
  • Beards are not as large;
  • May point their head down when flaring;
  • Wider and shorter than males;
  • Show vertical stripes when ready to mate; and
  • Will have an egg spot between their ventral and anal fins once fully matured.

Is This Going To Be A Community Tank?

Betta fish are territorial and aggressive, but they are capable of getting along with other species of fish. It’s important that fish owners research which fish will work best with the bettas to avoid unintended fights and potential deaths.

The personality of the other fish you are thinking about adding to the tank has to be considered. Fish that like to nibble on the fins of others are a definite no-no. Also, larger, more colorful fish may seem intimidating to your bettas. This can cause aggression fighting in your tank.

You’ll also want to avoid goldfish and any fish that have fins similar to that of a betta. Any fish that requires drastically different water conditions than your betta should also not be considered.

Don’t worry, though. There are several types of fish that can live with bettas including:

  • Guppies;
  • African Dwarf Frogs;
  • Ghost Shrimp;
  • Some tetras; and
  • Some catfish.

Make sure to talk to your local pet store before purchasing any fish. You don’t want to have a tank full of fish fighting. It’s inhumane and expensive, to say the least.

If you’re struggling to decide which fish to put with your bettas, do the research first. And remember, every fish has different tank size requirements. When you introduce other species to the tank you’ll have to adjust the size of the tank for the space they’ll need.

Live Plants Or Oxygen Pump

Just like any other fish, your betta needs to have oxygen in the tank. Without oxygen, it will struggle to breathe and will likely just hang out at the bottom of the tank.

Keeping your bettas in a glass vase can make it difficult for them to get all of the oxygen they need. Unmoving, unfiltered water has less oxygen than clean, moving water.

Think of a pond and a river. Ponds tend to have less water movement and are often stagnant and smell terrible. When you’re next to a river though, you can sometimes see straight to the bottom and it smells fresh and clean.

It’s the same with the water in your pet’s tank.


It’s important to have a proper filtration system (like this one) in your betta’s tank. The murkier the water is, the less room there is for oxygen. Some people will change the water in their tank more often if they don’t have a water filter, and this can work.

However, if you can’t commit to changing the water out every couple of days a filtration system is definitely the way to go in a smaller tank.

The larger the tank is, the larger your filter will need to be. The filter that can efficiently clean a 10-gallon tank is not going to work nearly as well on a 50-gallon tank. Sometimes you may even want to have more than one filter running at a time.

Keep in mind the more fish that you have in your tank, the quicker it will get dirty. Fish waste can be a serious problem for the quality of the water in your tank.

If you have a large community of fish or more than one in a small tank, the water will get dirtier much faster with disastrous results. This will mean you require a larger filter or you’ll have to clean the tank more often.

If you add bottom feeders to the mix it will help with the natural filtration of the tank. Just remember they have to be compatible with your bettas!can I keep betta fish in a small tank?

Live Plants

Live plants are a great way to add to the tank’s ecosystem. Not only do they look beautiful, but they also add oxygen to the tank while filtering out harmful things like carbon dioxide and ammonia.

Depending on your personality, you may want to get plants that are low maintenance. This means you’ll want to stick to green plants for your tank. If you want to have red plants in your tank you will have to adjust nutrients and lighting so they can remain healthy.

This may have a negative effect on your bettas or other fish.

Fortunately, there is a variety of plants to choose from including:

  • Amazon Sword
  • Java Fern
  • Water Wisteria
  • Java Moss; and
  • Green Tiger Lotus

If you want other options, make sure you talk to someone from the fish department at your local pet store.

Oxygen Pump and Air Stone

Another way to get oxygen into the tank is to purchase a pump (this pump is a bargain – click here). Pumps will circulate the water in the tank and bring oxygen to all corners of your tank. If you have a large tank you may need more than one pump to keep the water properly circulated.

If you want a more decorative look, you can always go for an air stone like this one. These can be a lot more fun and bring a lot of oxygen (and personality) to the tank.

Air stones are not really stones, they are decorations that have a small pump inside them that releases bubbles of air into the tank. A common decoration is the treasure chest that releases a bubble every thirty seconds or so.

Are You Dividing Your Tank Up?

One way that some fish owners keep several male bettas in their tank at a time is by dividing their tanks into sections.

There are many DIY ways to create dividers in your fish tank. You can also purchase tank dividers here if you’re not extremely crafty.

A 20-gallon tank can be divided into four 5 gallon tanks using only three dividers. With four areas to house fish, you can keep several males, or a few sororities of females, too.

Benefits Of Dividing A Tank

When you divide up a fish tank you’ll have a material that the water can flow through. This means that while the fish cannot get through the dividers, the filtration system can still work as can any oxygen pumps you put into place.

This will mean there is less maintenance for you. Having several separate tank setups means double or triple the work in upkeep so your fish remain healthy. With one big tank divided up, you’ll only need to maintain that one.

Another benefit is that you can own several species of fish that normally can’t cohabitate. If you want to have some goldfish and some bettas, you can do that with a divided tank.

It’s also handy if you’re breeding your bettas. Rather than have the male live in its own separate tank, you can have it living next door to the females. This will make the transfer in and out of the female’s tank much quicker and easier.

What To Consider When Picking Out Divider Material

Anytime you add anything to your tank you have to consider how the material may affect your fish.

For example, if you choose to use perforated cardboard to divide up your tank, it will eventually rot and disintegrate. Some metals will also rust or oxidize, releasing dangerous chemicals into your fish’s ecosystem.

Plastic, acrylic or silicone dividers work the best, just make sure there are no jagged edges that the bettas can catch their fins on.

Your dividers will also need to limit visibility. If your male bettas see each other, they will get stressed out. Agitated and stressed out fish are similar to humans. Undue stress will have negative effects on their health.

Also, the betta may try to attack the fish through the divider. This can lead to injuries and potentially damaged dividers.

If there is no airflow between the dividers you might as well have several different tanks. The oxygen and water need to be able to move around freely in the tank. This means that while your divider needs to block the sight of the other fish, it still has to allow circulation.

No circulation means more work for you.

You’ll want to make sure your dividers are going to stay in place when you put them in the tank. When purchasing dividers, some of them come with suction cups to hold the divider in place.

Make sure they are securely in place, because if they slip your fish will fight and you’ll have to buy new bettas.

There are other ways to hold your divider in place besides suction cups. Some people cut the material to the exact size and glue it into place. Others hold it in place with decorations or binder clips at either end that have been glued into place.

Just double-check the chemicals in the glue. You don’t want to introduce hazardous chemicals into the tank with your fish. Also, some glues may break down over time if they remain submerged in water.

Finally, you’ll want to make sure it’s a complete divider. This might seem like a no-brainer, but if there is even a centimeter of water over the top the fish may see each other.

Betta fish have been known to jump, so there is nothing stopping them from jumping the divider and attacking its neighbor.

It should also cover from side to side completely. Any wiggle room on either side of the tank can mean fish fights or injuries.what tank size do betta fish need?

Drawbacks Of Dividers

The biggest consideration here are diseases. Unlike housing your betta fish in separate tanks, when one fish falls ill, it will spread throughout the tank.

This is really no different than having a regular community of fish in an undivided tank, but with the dividers in place, it might be easy to forget that they’re all living in the same water.

The other thing to consider is that sometimes even though a betta cannot see the other fish in the tank, they can still sense that it is there.

They don’t have a great sense of smell, but if both are hanging out at the divider, they are close enough to smell any waste the other fish might be releasing.

This can cause stress for your fish and may lead to illness or listlessness. If that happens, you may need to consider returning to separate tanks for your little ones.

In Summary

Betta fish are just like any other fish. They have their own health requirements and their own personalities. Besides that, they are also extremely intelligent and can even learn to interact with humans – read our article on that here!

A small tank will not give your fish the freedom it deserves and you are putting its health at risk when you do so.

Avoid the 1 or 2-gallon vases and get yourself a proper 5-gallon tank for your betta. They will have longer, happier lives.

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