3 Gallon Fish Tank Ideas – Top Recommendations From Experts

Many aquarists enjoy having a tank of their own, but some cannot afford a standard 10-gallon tank. In this case, buying a small-sized, 10-gallon tank is highly recommended. Despite its limited space, such a tank can still host several species if you are skillful enough.

In today’s article, let’s have a look at some 3-gallon fish tank ideas. Check out what professional aquarists have to share and see if they can be useful for you!

Best 3-Gallon Fish Tank Ideas For Starters

Asian stone catfish

Asian stone catfish

With an average length of roughly 1 inch, it is safe to say that Asian stone catfish make quite an addition to your 3-gallon tank. Despite their seemingly unnoticeable color, Asian stone catfish pride themselves on having protruding whiskers that make them stand out.

Given the size of your aquarium, a small group of roughly 3 to 4 fish will suffice.

Fancy guppies

As the name already indicates, fancy guppies catch your attention with their large, fluffing tails and bright pastel colors. By nature, they are peaceful and relatively quiet, which creates perfect harmony in your community tank.

The only thing you should be concerned about is their reproductive patterns. It is best to keep only 2 to 3 males in a tank at the same time.

Endler’s livebearer

If you wish to add a visually pleasing species, nothing beats the Endler’s livebearer. All it takes is one look at these animals and you will understand why they are widely popular. With vibrant and illuminating colors, Endler’s livebearers are a sight to behold.

However, it should be noted that this species reproduces rather quickly. To prevent overcrowding your tank, make sure to keep only the endler’s livebearers of the same sex.


Tetras are the go-to choices when it comes to 3-gallon tanks. Not only are these fish small and easy to live with most other animals, but they are also colorful and eye-catching.

Since tetras do not travel on their own, it is vital that you keep at least 3 to 4 of them together. And remember to provide tetras with several driftwood or plants for shade and munching!

Betta fish

Betta fish are cheap, easy to come up with, and generally beautiful. Thus, it is no surprise that these animals are beginner-friendly for aquarists. Furthermore, they are tiny in size, making them the perfect choice for a small-sized tank.

That said, betta fish do not do well if put in a large community tank. To avoid conflicts, you are advised to keep no more than 2 bettas in your aquarium.

Pygmy gourami

Pygmy gourami

Pygmy gourami has an elongated body with silvery skin. They are about 1.5 inches in length and do not require much special treatment. Thus, these animals are suitable for a small community tank. But still, you would need to watch out for the lighting, as pygmy gourami do not thrive well when overlit.

Zebra danio

These fish are best known for their stripes running along the body, giving them the name zebra. With white and neon blue spots mixing together, zebra danio is fun and entertaining to watch.

Even better, they are hardy and easily adaptable. The only thing you have to be careful about is maintaining suitable temperatures and pH levels.

How Many Fish In A 3-Gallon Tank Is Enough?

Generally speaking, you can put around 3 1-inch fish in such a small tank. This is because of the “1 inch of fish per one gallon of water” rule. Most people believe that this level of density is ideal for fish to survive and live well.

However, other factors should be considered as well. For example, invertebrates tend to be small in size and live mostly at the bottom of the tank.

Hence, they can be good company for slightly larger fish such as bettas. Or some fish require dense vegetation and driftwood to survive. If the tank is a bit overcrowded, you cannot possibly put in 3 fish.


1. Can you keep a betta fish in a 3-gallon tank?

Yes. By no means are bettas the largest fish to put in an aquarium. They are small, hardy, and easy to care for. That is not to mention how lively and colorful these animals are.

But still, you do not want to create a chokehold by putting in more than 3 or 4 of them. Bettas prefer lots of plants to hide and drift around. If the 3-gallon tank is already filled with such objects, keep the number of bettas at 2 so they can live comfortably.

2. What to put in a 3-gallon tank with bettas?

If you intend to put one betta in a 3-gallon tank and want some companions, consider tetras, rasbora, or corydoras. The difference in their most-frequented areas and traveling speed will prevent collisions.

They are also relatively peaceful and do not engage in many aggressive behaviors. Hence, mixing them with bettas is highly recommended.

3. What fish do not live in a 3-gallon tank?

small fish tank

While there are fish compatible with the size of such a tank, others are not that easy-going. Some fish are too big when they reach adulthood, making the 3-gallon tank tiny and overcrowding. Some only feel safe when traveling in a group of more than 3, thus compromising the potential of a 3-gallon tank.

Whatever you wish to keep in your aquarium, you should research them beforehand and see whether they can cope with the tank’s limited space.


Now that you have grasped the most exciting 3-gallon fish tank ideas, it is time to build an aquarium on your own. Check out the local store and see if they have what you intend to buy. In no time, you will get to enjoy a mesmerizing tank!