If you’re ready to set up your new nano tank, then you’re probably wonder what the best fish for a 5 gallon tank are! Y4ou’re in the right place. We will talk about the best fish for a small tank like yours. We’ll talk about how to care for them, how they act, and if they get along with other fish.
Whether you’re an expert or starting out, we’ve got your back. So let’s dive in and find the best fish for your 5-gallon tank.
How Many Fish Can You Put In 5 Gallon Tanks?
If you plan to get a 5-gallon tank, remember that having around 2-4 small fish there is best. You want them to be a maximum of 1 inch, though. Otherwise, they need more space to move around.
A standard rule of thumb is 1-inch of fish per gallon of tank water. This rule usually applies to small fish like Tetras, Betta, Rasbora, Shrimps, and others.
But, you gotta be careful because any fish that can grow bigger than 1 inch won’t do well in a 5-gallon tank.
What Are The Best Fish For 5-Gallon Tanks?
Because of the limited space, you must choose your fish carefully if you consider setting up a 5-gallon tank. Here are some fish that would be perfect for a small tank:
Guppies

These friendly fish are a great complement to any 5-gallon tank. They are quick, playful swimmers who prefer to hang out towards the tank’s top or around plants. Guppies are ideal for small community aquariums because they aren’t considered aggressive.
Name | Guppies |
pH | 6.8-7.8 |
Temperature | 74-82°F |
Size | 1.5-2.5″ |
Lifespan | 1-3 years |
Difficulty Keeping | Easy |
Chili Rasbora

These little guys are super popular because of their small size and peaceful temperament, which makes them perfect for small tanks. They’re torpedo-shaped with a fiery red color and a dark line along their body. You might even see some small spots near their tail and anal fins.
One thing that’s really cool about Chili Rasboras is that they’re super active. They spend all day swimming and playing with each other, which means you’ll have a lot of fun watching them in your tank. Plus, their small size means you can keep a few in a 5-gallon tank without worrying about overcrowding.
Name | Chili/Mosquito Rasbora |
pH | 5.0-7.0 |
Temperature | 72-82°F |
Size | 1.25″ |
Lifespan | 4-8 Years |
Difficulty Keeping | Easy |
Dwarf Pea Puffer

Dwarf Pea Puffers, also known as Pygmy Puffers, are delightful little fish that also do well in a 5-gallon tank. Be warned though, they’re best kept in a species only tank as they’ll attack almost any other fish in the tank.
Despite their small size, they possess big personalities and are known for their curious nature. Just keep in mind that Dwarf Pea Puffers are carnivorous and prefer a diet of small live or frozen foods. They also appreciate a well-planted tank to explore and hide in.
Name | Dwarf Pea Puffer |
pH | 6.5-8.5 |
Temperature | 74-82°F |
Size | 1.4″ |
Lifespan | 4-5 years |
Difficulty Keeping | Easy |
Least Killifish

If you’re looking for a more small and peaceful nano fish for your 5-gallon tank, the Least Killifish may just be the perfect choice. These tiny fish, also known as Dwarf Livebearers, have a gentle temperament and bring a touch of elegance to any aquarium.
With their shimmering colors and graceful movements, they create a captivating display. These fish are relatively low-maintenance, but they do best in a well-maintained tank with plenty of hiding spots and vegetation.
Name | Least Killifish |
pH | 7.0-8.0 |
Temperature | 68-78°F |
Size | 1.2″ |
Lifespan | 3 years |
Difficulty Keeping | Easy |
Strawberry Rasbora

Strawberry Rasboras, with their striking red hues, are another beautiful addition to a 5-gallon aquarium. These small, peaceful fish are known for their schooling behavior and should be kept in groups of 6 or more.
Watching them swim together is a delightful sight, as they gracefully glide through the water. Just remember, despite their small size, they appreciate a well-planted tank with open swimming space. And lastly, keeping Strawberry Rasboras in a group will allow them to display their natural behavior and add liveliness to your aquatic oasis.
Name | Strawberry Rasbora |
pH | 5.5-7.0 |
Temperature | 77-82°F |
Size | 0.7″ |
Lifespan | 8 years |
Difficulty Keeping | Easy |
Dwarf Rasbora

Dwarf Rasboras are another fantastic freshwater fish option for a 5-gallon tank. These tiny fish, similar in size to Chili/Mosquito Rasboras are going to bring a splash of color and vitality to any nano tank.
They come in shades of red and orange which are sure to captivate anyone’s attention. Despite their small size, they are active swimmers and love to explore their surroundings. With their peaceful nature, Dwarf Rasboras can coexist with other compatible tank mates, making them great fish for a community tank!
Name | Dwarf Rasbora |
pH | 5.0-6.5 |
Temperature | 68-82°F |
Size | 2.5″ |
Lifespan | 3-5 Years |
Difficulty Keeping | Easy |
Asian Stone Catfish
For a unique and fascinating addition to your tank, consider the Asian Stone Catfish. These small catfish, also known as Hara Jerdoni, are known for their camouflage and ability to blend into their surroundings.
With their stone-like appearance, they bring an element of surprise to your aquarium. Asian Stone Catfish are relatively peaceful and enjoy hiding in crevices and caves. They prefer a well-established tank with plenty of hiding places and a sandy substrate to mimic their natural habitat.
Name | Asian Stone Catfish |
pH | 5.6-7.6 |
Temperature | 65-75°F |
Size | 1.5″ |
Lifespan | 5 Years |
Difficulty Keeping | Easy |
Clown Killifish
These micro predators are super interesting to watch because they don’t care about plants or vegetation – they prefer to hang out at the surface and chow down on insects and other critters.
Not only are they fascinating to observe, but they’re also pretty eye-catching themselves. With their long, rocket-shaped bodies splashed with colors ranging from black and yellow to blue and red, they will surely add some pizzazz to your tank. The colors are usually in a striped pattern and will be more vibrant in males than females. Fin colors can also vary.
One great thing about Clown Killifish is that they’re so small – you can keep a group of three in a 5-gallon tank without any problems. So if you want a small but mighty addition to your aquarium, the Clown Killifish is what you’re looking for!
Name | Clown Killifish |
pH | 4.0-7.0 |
Temperature | 68-79°F |
Size | 1.4″ |
Lifespan | 2-3 years |
Difficulty Keeping | Easy-Intermediate |
Betta Fish

These little guys are also known as Siamese Fighting fish, and they definitely live up to their name. Betta fish are stunning to look at but highly territorial, so it’s not recommended to keep two males together in the same tank. But don’t worry; you can still enjoy the beauty of Betta fish by keeping a single male in your 5-gallon tank.
To add some extra color and activity to your tank, consider adding a couple of Cherry shrimp as tank mates. These little critters will help keep your tank clean and add a nice pop of color to your underwater world. Just provide plenty of hiding spots for your shrimp, as the Betta may see them as a potential snack.
Name | Betta |
pH | 6.5-7.5 |
Temperature | 76-80°F |
Tank Size | 5 Gal |
Size | 2.5-3″ |
Lifespan | 3-5 Years |
Difficulty Keeping | Easy |
Other Tank Mates For A 5 Gallon Tank
A 5-gallon tank is not just limited to fish. You have the option to create a flourishing underwater environment by including invertebrates.
African Dwarf Frog

If you’re interested in keeping something in your tank that isn’t a fish then African Dwarf Frogs are a great choice. These tiny little amphibians have an endearing appearance and are known for their inquisitive nature.
African Dwarf Frogs are relatively easy to care for and enjoy a habitat with plants, hiding spots, and gentle filtration. Watching them gracefully swim and interact with their surroundings can be a fascinating experience.
One thing to note about African Dwarf Frogs is that they should never be kept alone, so make sure you’re keeping a minimum of two. While it is possible to keep two in a 5 gallon tank, a 10 gallon tank is much more ideal as well.
Name | African Dwarf Frogs |
pH | 6.5-7.5 |
Temperature | 75-82°F |
Size | 2.5″ |
Lifespan | 5 Years |
Difficulty Keeping | Easy |
Cherry Shrimp

Cherry Shrimp are hardy and adaptable, making them ideal for beginners. They are colorful and active, adding vibrancy to the tank. These shrimp are excellent at cleaning algae and leftover food, so they help keep the tank clean.
Name | Cherry Shrimp |
pH | 6.5-8.0 |
Temperature | 72-82°F |
Size | 1.25″ |
Lifespan | 1-2 years |
Difficulty Keeping | Easy |
Amano Shrimp

Amano Shrimp are another excellent choice for a 5-gallon tank, however they do a lot better when kept in 10 gallon tanks. They are larger than Cherry Shrimp but are still relatively small and can coexist with other invertebrates. Amano Shrimp are also great at cleaning algae and keeping the tank clean.
Name | Amano Shrimp |
pH | 6.0-7.5 |
Temperature | 65-85°F |
Size | 2″ |
Lifespan | 2-3 years |
Difficulty Keeping | Easy |
Ghost Shrimp

Ghost Shrimp are hardy and easy to care for, making them another great option for a 5-gallon tank. They are transparent, making them an exciting addition to the tank. They are also great at cleaning up leftover food and debris.
Once again, while a 5 gallon tank can work, they are going to do much better in a 10 gallon tank.
Name | Ghost Shrimp |
pH | 7.0-8.0 |
Temperature | 65-80°F |
Tank Size | 5 Gal |
Size | 1.25″ |
Lifespan | 1-2 years |
Difficulty Keeping | Easy |
Mystery Snail

Mystery Snails are a peaceful and easy-to-care-for snail species that can thrive in a 5-gallon tank. They are excellent at eating algae and decaying plant matter, which helps keep the tank clean.
Name | Mystery Snail |
pH | 7.0-8.0 |
Temperature | 68-82°F |
Size | 2″ |
Lifespan | 1-2 years |
Difficulty Keeping | Easy |
Nerite Snail

Nerite Snails are another popular snail species that are ideal for small tanks. They are great at eating algae and keeping the tank clean. However, remember that Nerite Snails need hard water to maintain healthy shells.
Name | Nerite Snail |
pH | 7.0-8.0 |
Temperature | 72-78°F |
Size | 0.75″ |
Lifespan | 1-2 years |
Difficulty Keeping | Easy |
5 Gallon Tank Fish Combinations
A 5-gallon tank is pretty small, so you won’t be able to keep a whole bunch of fish in there. In fact, it’s generally recommended that you only keep one or two fish in a tank this size.
Here are a few combinations of fish that could work well in a 5-gallon tank:
- Betta fish: Betta fish are colorful and have prominent personalities. They’re also pretty hardy and can do well in a smaller tank. You could keep one male Betta or a female in a 5-gallon tank.
- Shrimp and snails: If you’re not looking for fish, consider keeping some shrimp or snails in your tank. These creatures are great at keeping the tank clean and can be fun to watch as they move around.
- Guppies and a snail: Guppies are small, colorful fish that can do well in a 5-gallon tank. You could keep a small group of guppies (3-4) and a snail to help clean.
Remember, keeping your tank clean and well-maintained is essential, especially in a smaller tank like a 5-gallon. Make regular water changes and keep an eye on your fish to ensure they’re healthy and happy.
What Fish Should You Avoid Putting In 5 Gallons?
In getting fish for your 5-gallon tank, there are a few types that you should avoid.
1. Goldfish – They look cute and tiny but hate being alone and need more space to swim around. Keeping them in a 5-gallon tank would make them pretty unhappy.
2. Cichlids – There are also better choices for small tanks. They can be aggressive and need a lot of space to swim and establish their territories. Even if you only keep a pair of cichlids together, they will constantly fight each other because of the cramped space.
3. Angelfish – It can grow up to 6 inches long and needs a lot of swimming space too. They can be aggressive, especially when it comes to establishing their territory. You would need at least a 29-gallon tank to keep one angelfish happy.
So, it’s better to avoid more extensive or aggressive fish in a 5-gallon tank and opt for smaller, peaceful fish such as guppies or tetras.
As well as the above, I’ve noticed a lot of people saying that you can keep all of the following fish in a 5 gallon tank (however, this simply isn’t true):
- Endler’s Livebearers – Need a 10 gallon tank.
- White Cloud Mountain Minnows – Need a 10-15 gallon tank.
- Neon Tetras – Need a 10 gallon tank (but ideally 15).
- Cardinal Tetras – Need a 20 gallon tank.
- Harlequin Rasboras – Need a 10 gallon tank.
- Celestial Pearl Danios – Need a 10 gallon tank.
- Ember Tetras – Even though they’re small, they’re active schooling fish which need 10 gallons minimum.
- Bumblebee Gobies – Need to be kept in 10 gallon tank minimum.
As you can see all of these fish need a 10-gallon tank or bigger!
What Are The Problems With A 5-Gallon Tank?
While small tanks can be fantastic for certain fish and plants, they come with challenges. We’ll check out some potential problems you might encounter, like water quality issues, limited space, and maintenance headaches.
- Only a little space: A 5-gallon tank is pretty small, so you won’t be able to fit many critters or plants in there. This can make it tough to create a good home for your animals and limit what you can keep.
- Water quality issues: Keeping water quality stable in a small tank is harder. The water parameters can change quickly, so you’ll need to monitor things closely and do water changes more often.
- Temperature troubles: Small tanks can also be tricky to keep at the right temperature. Because there’s less water, the temperature can change more easily and quickly.
- Plant problems: Some plants might not thrive in a 5-gallon tank. They might not do well if they need a lot of space or nutrients.
- Maintenance: It is tough to clean and change the water in a small tank without disturbing everything and stressing your fish.
A 5-gallon tank can be a good choice for small animals or plants, but you must be careful about what you choose and work hard to keep things healthy.

What Will Your 5-Gallon Tank Need?
If you’re thinking about setting up a 5-gallon tank, there are a few things you’ll need to keep in mind. What you’ll need will depend on what you plan to keep in the tank, but here are some general guidelines:
Purchasing An Aquarium Kit
Generally, at 5 gallons, it can often be better to buy an aquarium kit which comes with most of the stuff you’ll need to get started. When looking for one, make sure to choose one with a lid. Not only will this stop certain fish jumping out, but it will also reduce water evaporation, and a lot of times they also house a light too!
- FUN and REWARDING: Are you looking to buy an aquarium for your children? If you are, you are going to want to look at this fish tank. Owning an aquarium can be a really fun and rewarding experience and an ideal way to teach your child the responsibility of pet ownership.
- DAZZLING COLORS: Energy-efficient LED lighting with 7 dazzling color selections to brightly illuminate your fish, choose daylight white, blue, green, amber, aqua, purple, or red.
Invest in a Quality Filter for Clean Water
First of all, in a tank so small you’re going to need to make sure you’re using a high quality filter. Tanks of this size can have fluctuations in their parameters incredibly fast, so a good filter is essential.
And when you’re choosing a filter, be sure to choose one specifically designed for a 5-gallon tank to maximize its effectiveness. Generally speaking, you want the filter to be able to process 3-4 times the water in the tank an hour.
Lastly, while I like the Tetra Whisper Filter, for such a small tank, you can also consider sponge filters instead.
- UNIVERSAL DESIGN Tetra Whisper 10i Internal Filter is an all-in-one air pump and water filter system
- INTERNAL FILTER Mounts on the inside of your aquarium with clip (included)
Use A Heater & Thermometer
If you’re going to be keeping tropical fish, it’s also essential to make sure you’re using a heater too. Generally speaking you should aim for 5 watts per gallon of water when you’re picking a heater. But don’t just rely on the heater to tell you the temperature of the tank either.
You should also use a thermometer to make sure that the water in the tank is staying warm consistently too.
- All Tetra HT heaters have indicator lights to let you know when the heater is on. It will be red when heating and green when the proper temperature has been reached..All Tetra HT Heaters will shut off if an electrical short is detected for your safety.
- The HT10 uses a built in electronic theromstat to automatically maintain water at 78° F which is ideal for most tropical fish. No adjustment is requried.
Pick The Right Substrate
You should also make sure that you’re picking the right substrate for the tank as well. I personally love to use aquarium soil because I like a planted tank, however, you can also choose between gravel and sand too.
If you have a lot of bottom dwellers then sand may be best, but if not, then most substrate is going to be good for your tank!
- Fluval Stratum is made of mineral rich volcanic soil
- Stimulates strong aquarium plant growth
- Promotes neutral to mildly acidic pH
- Suitable for live plants or shrimp
- 8.8 lb. bag
Lighting
Lighting is essential not just for the plants in your tank, but also the fish. Just like us fish have a circadian rhythm so if you’re not giving them enough light every day it will mess up their body clock. Also not giving your fish light can also cause them to become more pale and lose their color.
- DEFAULT MODE(24/7 Natural Mode): Gradient Orange light (sunrise) from 6 am to 8 am; Gradient White light from 8 am to 6 pm; Gradient Blue light (moonlight) from 6 pm to 10:50 pm; The 24/7 lighting aquarium lights are off in other time periods. The overall default time period can be delayed or advanced.
Water Conditioner
You should always make sure you’re conditioning water before you add it to your tank as well. I like to use API Stress Coat. Not only does it treat tap water, but it also helps reduce stress in your fish as well.
- Contains one (1) API STRESS COAT Aquarium Water Conditioner 16-Ounce Bottle
- Makes tap water safe and protects fish with dual-action formula
A Water Test Kit
And lastly, you’re also going to need a water test kit to ensure the parameters in your tank are always as they should be. Water test kits are going to help you measure the ammonia, nitrite, nitrate and pH levels in the tank. In small fish tanks I’d do this weekly as conditions in the tank can change a lot more rapidly.
- Contains one (1) API FRESHWATER MASTER TEST KIT 800-Test Freshwater Aquarium Water Master Test Kit, including 7 bottles of testing solutions, 1 color card and 4 tubes with cap
- Helps monitor water quality and prevent invisible water problems that can be harmful to fish and cause fish loss
Fish Food
The fish food you choose, will depend entirely on what you add to your tank. Bettas are going to need specific betta pellets, where as shrimp will do a lot better with algae wafers and blanched vegetables. However, in most cases, flake food is going to be more than adequate!
And don’t forget to feed your fish live and frozen food like blood worms, daphnia, brine shrimp, and mosquito larvae!
- TROPICAL FORMULATION: Highly digestible ingredients for use as staple food for your top- and mid-feeding tropical fish.
FAQ
Are 5 Gallons Big Enough For A Betta?
A 5-gallon tank is actually a great size for a single betta. It’s not too big or too small, and it’s easy to keep clean and maintain. So if you’re considering getting a betta, a 5-gallon tank is the perfect home for them!
How Long Must You Wait To Put Fish In A 5-Gallon Tank?
In adding some fish to a brand new tank, you’ll want to wait at least 24 to 48 hours before doing so. But it’s better to wait up to a week if you can. During this time, your tank will go cycling, which helps build up good bacteria that keep your water clean and healthy for your fish.
How Often Should You Clean A 5-Gallon Fish Tank?
In a 5-gallon fish tank, you should do a partial water change of about 25% once a week. You can also do a more thorough cleaning every 3-4 weeks. Be careful not to clean everything at once, or you could disrupt the good bacteria in your tank.
What Temperature Should A 5-Gallon Fish Tank Be?
You should aim to keep the water temperature between 75-80°F (24-27°C) in a 5-gallon tank. This range is generally comfortable for most common tropical fish. It’s essential to use a reliable thermometer to monitor the temperature and adjust as needed.
What Is The Easiest Fish To Care For In A 5-Gallon Tank?
Betta fish are small-space champs! They don’t need a huge aquarium to be healthy and thrive. In fact, they’re used to cramped and shallow environments, making them perfect for 5-gallon tanks.
Is A 5-Gallon Tank Okay For A Goldfish?
Goldfish are gorgeous but not the best fit for a small 5-gallon tank. These guys are poop machines; their waste can quickly turn your tank into a danger zone. Ideally, you should go for a tank between 20 and 40 gallons to give your fish plenty of room to swim around.
Can Angelfish Live In A 5-Gallon Tank?
Angelfish are total bullies and will nip at their tank mates and fight like crazy for territory, which means they’ll be under constant stress if kept in a 5-gallon tank.
How Many Guppies Can You Put In A 5-Gallon Tank?
You can have at least two, but at most five guppies in a 5-gallon tank. If you’re new to fishkeeping, stick with the lower end of that range. But if you’ve got some experience, try keeping five.
Conclusion
When adding some fish to your small tank, doing some research beforehand is essential. You want to make sure you choose fish species that can live comfortably in a smaller space and that you can take good care of.
Plenty of options exist, but we’ve got you covered with some suggestions. Regular water changes and monitoring ammonia and nitrate levels are vital to keeping your fish healthy in the long run.
You and your fish can enjoy a happy and healthy life together in your small tank with the proper care!
Lastly, remember, 5 gallons is the minimum tank size you should be putting freshwater aquarium fish in. Anything smaller than this is going to be unhealth and even dangerous for them.