If you’re a beginner fish owner, small fish tanks might seem for many reasons, especially if you don’t have enough space for a larger one. However, it’s important to understand the basics of keeping fish in small tanks to ensure the well-being of your pets.
This article will cover the minimum tank size for fish, the number of fish that can be kept per gallon, the best fish for different tank sizes, and many more! So keep reading to find out!
What’s The Minimum Tank Size For Fish?
The minimum tank size for fish varies depending on the type of fish you want to keep. Some fish species are small and can survive in tanks as small as 5 gallons, while others require much larger tanks.
For example, small, peaceful fish like bettas, neon tetras, and guppies can thrive in a 5 to 10-gallon tank, while larger fish like angelfish and discus require at least 20 to 30 gallons of water.
It’s essential to research the specific requirements of the fish you want to keep before purchasing a tank. Make sure you have a tank that is large enough to provide enough space and water quality for your pets.
A Quick List Of The Best Fish For Small Tanks
If you’re short on time, here’s a quick list of the best fish you can keep in small fish tanks! However, keep reading to find out how to care for them properly.
- Betta Fish
- Guppies
- Neon Tetras
- Cherry Shrimp
- Trumpet Snails
- Pygmy Corydoras
- Harlequin Rasboras
- Ember Tetras
- Platies
- Mollies
- Zebra Danios
- Bumblebee Gobies
- Siamese Algae Eaters
- Otocinclus Catfish
- Amano Shrimp
- Nerite Snails
- Plecos
How Many Fish Can You Keep Per Gallon?
The number of fish you can keep per gallon depends on the size and water requirements of the fish. A general rule of thumb is to have 1 gallon of water per inch of fish. This means that a 5-gallon tank can comfortably house 2 to 3 small fish, while a 10-gallon tank can house 10 to 12 small fish.
However, this is not a one-size-fits-all kind of rule. It’s also important to consider the bioload, or the amount of waste produced by the fish, in determining the number of fish that can be kept in a tank. A higher bioload means that more filtration is needed to maintain water quality and prevent the build-up of harmful toxins.
What Are Good Beginner Fish For Small Tanks?
For those just starting out with fish keeping, it’s best to choose fish that are hardy and require little effort to care for. Some popular beginner fish for small tanks include:
- Bettas: Also known as Siamese fighting fish, bettas are colorful, hardy fish that are ideal for small tanks. If you have a 5-gallon tank, they’re going to be the perfect fish for this size! Just make sure you’re keeping them on their own.
- Neon tetras: Another great choice, these small, brightly colored fish are popular for their vibrant colors and peaceful nature. They are hardy fish that require little care and can be kept in tanks as small as 5 gallons, however, it’s recommended to keep them in a tank that is a minimum of 10 gallons in size.
- Guppies: Lastly, guppies are another small fish that are easy to care for and they also come in a variety of great colors. They are ideal for small tanks and can be kept in tanks as small as 5 gallons.
Best Fish For 5-Gallon Tanks
Keeping fish as pets can be a fun and rewarding hobby. However, it’s important to choose the right fish for your tank size to ensure the health and well-being of your aquatic pets. A 5-gallon tank is a small aquarium and requires careful consideration when selecting the fish to keep in it. In this article, we will explore some of the best fish for 5-gallon tanks.
Betta Fish
Betta fish, also known as Siamese fighting fish, are a popular choice for small aquariums due to their small size and beautiful colors. They can grow up to 2.5 inches in length and are known for their vibrant and colorful fins.
Betta fish are also relatively hardy and can tolerate a wide range of water conditions, making them a great option for beginners. However, it’s important to note that betta fish are solitary creatures and should not be kept with other fish as they’re territorial and can become aggressive towards other fish in their tank.
Requirements
- Temperature: 72–82°F
- pH: 6.5-7
- Tank Size: 5 gallons and higher
- Fish Size: 2.5 inches
- Lifespan: 2-4 years
- Difficulty Keeping: Moderate
Guppies
Guppies are another popular fish for small tanks due to their small size and hardiness. They can grow up to 2 inches in length and are known for their vibrant colors and active swimming behavior.
Guppies are also livebearers, which means they give birth to live young, making them a great option for those looking to breed fish. Additionally, guppies are social fish and can be kept in small groups, which can add to the aesthetic of your aquarium.
Requirements
- pH: 6.8–7.6
- Temperature: 74–82°F (23–28°C)
- Tank Size: 5 gallons and higher
- Fish Size: 0.6-2 inches
- Lifespan: 2 years
- Difficulty Keeping: Easy
Neon Tetra
Neon tetras are small and colorful fish that are a popular choice for small aquariums. They can grow up to 1.5 inches in length and are known for their bright neon blue and red stripes.
Neon tetras are also active swimmers and can add movement to your aquarium. They are best kept in small groups of at least 6, as they are social fish and will feel more comfortable in a school.
Requirements
- pH: 6.0–7.0
- Temperature: 70–81°F (21–27°C)
- Tank Size: 5 gallons and higher
- Fish Size: 1-1.5 inches
- Lifespan: 6-8 years
- Difficulty Keeping: Easy
Cherry Shrimp
Cherry Shrimp can be a great addition to a 5-gallon tank, adding both color and interest to your aquarium. There are many different types of shrimp available, including cherry shrimp, ghost shrimp, and Amano shrimp.
Another great thing use for shrimp are how helpful they are in cleaning your tank, as they feed on uneaten food and other debris, keeping your water clean. Additionally, shrimp are relatively hardy and can tolerate a wide range of water conditions, making them a great option for beginners.
Requirements
- pH: 6.5–8.0
- Temperature: 65–85°F (23–29°C)
- Tank Size: 5 gallons and higher
- Fish Size: 1.5 inches
- Lifespan: 1-2 years
- Difficulty Keeping: Easy
Trumpet Snails
Snails can also be a great addition to a 5-gallon tank, helping to keep it clean and adding interest. Aside from the trumpet snail, there are many different types of snails available, including mystery snails and nerite snails.
Snails are slow-moving creatures and will not outcompete your fish for food. Additionally, snails can help keep your tank free of algae, as they feed on it.
Requirements
- pH: 7.0–8.0
- Temperature: 68–84°F
- Tank Size: 5 gallons and higher
- Fish Size: 1 inch
- Lifespan: 1-2 years
- Difficulty Keeping: Easy
When choosing fish for a 5-gallon tank, it’s important to select species that are small and hardy, and will not outcompete each other for food and space. Remember to always research the specific needs and requirements of the fish you are interested in keeping, and consult with a knowledgeable aquarium professional if necessary.
In this video, you can find examples of 10 best fish for your 5-gallon aquarium.
Best Fish for a 10-Gallon Tank
When choosing fish for your 10-gallon tank, there are a few key factors to consider. Firstly, it’s important to choose fish that are well-suited to life in small tanks. This means that they should have small bodies and not need a lot of space to swim.
Secondly, you should look for fish that are easy to care for and that do not require a lot of special equipment. Finally, it’s important to consider the temperament of the fish, as some species can be aggressive and not well-suited to life in a small tank with other fish.
Pygmy Corydoras
Pygmy Corydoras are small, bottom-dwelling fish that have docile natures, and friendly personalities which make them a great choice for any tank! They’re also one of the best bottom feeders, and the perfect choice when looking for something to help keep the tank clean by eating any leftover food.
Requirements
- pH: 6.0–8.0
- Temperature: 72-79 °F
- Tank Size: 10 gallons and higher
- Fish Size: 1 inch
- Lifespan: 3 years
- Difficulty Keeping: Easy
Harlequin Rasboras
Harlequin Rasboras are another type of small, active fish that you will have no problem taking care of. and the best part is they’ll add plenty of color to your tank. And lastly, they’re peaceful fish which can be kept in a community of other small fish.
Requirements
- pH: 6.0–7.8
- Temperature: 72-81 °F (22-27°C)
- Tank Size: 10 gallons and higher
- Fish Size: 1.75-2 inches
- Lifespan: 5-8 years
- Difficulty Keeping: Easy
Ember Tetras
Ember tetras are another great fish to add to your community tank. they’re small, and peaceful, and most well known for their vibrant red bodies! You’ll have no problem caring for them just ensure that you’re keeping enough of them together!
Requirements
- pH: 5.5–7
- Temperature: 72-82 °F (22-28°C)
- Tank Size: 10 gallons and higher
- Fish Size: 0-5-0.8 inches
- Lifespan: 2-4 years
- Difficulty Keeping: Easy
Platies
Some of my favorite fish, platies are another great choice for small tanks, and you’ll be able to keep them in a tank that is 10 gallons or bigger.
However, be aware, if you’re keeping platies in your tank, they’re livebearers which means you may end up with a lot more in your tank than you first thought!
Requirements
- pH: 6.8–8.0
- Temperature: 70-77 °F (21-25°C)
- Tank Size: 10 gallons and higher
- Fish Size: 2-3 inches
- Lifespan: 2-3 years
- Difficulty Keeping: Easy
Dwarf Gouramis
Two or three dwarf gouramis are also going to fit perfectly in a 10-gallon tank and if you’re new to fishkeeping, they’re going to be a great choice for you thanks to how easy they are to care for! On top of this, they’re great to watch thanks to how active they are!
Requirements
- pH: 6.5–7.5
- Temperature: 75-81 °F (24-27°C)
- Tank Size: 10 gallons and higher
- Fish Size: 3.5 inches
- Lifespan: 3 years
- Difficulty Keeping: Easy
Best Fish for a 15-Gallon Tank
A 15-gallon tank is a great size for keeping fish, as it provides ample room for the fish to swim and allows for adequate filtration and oxygenation. If you are looking for the best fish for a 15-gallon tank, here are some options to consider:
Black Molly
These hardy fish are a great choice for a 15-gallon tank. They are easy to care for and are known for their hardiness and ability to adapt to different water conditions.
Requirements
- pH: 7.5–8.5
- Temperature: 72-78 °F (22-25.5°C)
- Tank Size: 10 gallons and higher
- Fish Size: 3-5-4.5 inches
- Lifespan: 3-5 years
- Difficulty Keeping: Easy
Corydoras
Corydoras are small catfish that are great for 15-gallon tanks. They are great at cleaning up the tank and are also known for their peaceful nature. Corydoras are a great addition to any community tank and can help keep the tank clean.
Requirements
- pH: 6.0-8.0
- Temperature: 72-78°F (22-25.5°C)
- Tank Size: 10 gallons and higher
- Fish Size: 1-2.5inches
- Lifespan: 3-5 years
- Difficulty Keeping: Easy
Zebra Danios
Zebra Danios are active fish that are great for a 15-gallon tank. They are known for their distinctive stripes and are great for adding color to the tank. Zebra Danios are some of the hardiest fish which make them a great choice for beginners.
Requirements
- pH: 6.8–8.0
- Temperature: 64-77 °F (18-25°C)
- Tank Size: 10 gallons and higher
- Fish Size: 1-5-2.5 inches
- Lifespan: 3-5 years
- Difficulty Keeping: Easy
Bumblebee Gobies
Bumblebee Gobies are small, colorful fish that are great for a 15-gallon tank. They are known for their distinctive yellow and black stripes and are great for adding a touch of color to the tank. Bumblebee Gobies are hardy fish and are easy to care for.
Requirements
- pH: 7.0–8.5
- Temperature: 72-84 °F (22-29°C)
- Tank Size: 10 gallons and higher
- Fish Size: 0-5-0.8 inches
- Lifespan: 3 years
- Difficulty Keeping: Easy
When choosing fish for a 15-gallon tank, it is important to keep in mind the size of the fish and the water conditions they require. It is also important to choose fish that are compatible with each other and to avoid aggression due to overstocking.
Best Algae Eaters For Small Tanks
Algae are common pests in aquariums and can take over a small tank in no time. The presence of algae in a tank can affect the growth and health of aquatic plants and animals. To control the growth of algae, it is important to have a few algae eaters in the tank. Here are some of the best algae eaters you can put in your tank.
Siamese Algae Eater
The Siamese Algae Eater is one of the most popular and effective algae eaters for small tanks. It is native to Southeast Asia and is known for its ability to eat a variety of algae types, including black beard algae and green algae.
This fish is also hardy, making it a great choice for new aquarium owners. The Siamese Algae Eater is a peaceful fish that will not harm other inhabitants of the tank. They are also social fish and prefer to live in schools, so it is recommended to have at least three in a tank.
Requirements
- pH: 6.5–8.0
- Temperature: 75-79 °F (24-26°C)
- Tank Size: 44 gallons and higher
- Fish Size: 6.3 inches
- Lifespan: 10 years
- Difficulty Keeping: Easy
Otocinclus Catfish
Otocinclus Catfish is another excellent option for a small tank. It is a small, hardy fish that is native to South America and is known for its ability to eat a variety of algae, including green algae, brown algae, and diatoms.
The Otocinclus Catfish is a peaceful fish that will not harm other inhabitants of the tank, and it also prefers to live in schools. This fish is very small and can be difficult to spot in a tank, so it is important to observe the tank regularly to make sure that it is getting enough to eat.
Requirements
- pH: 6.8–7.5
- Temperature: 72-79 °F (22-26°C)
- Tank Size: 10 gallons and higher
- Fish Size: 1-2 inches
- Lifespan: 3-5 years
- Difficulty Keeping: Easy
Amano Shrimp
Amano Shrimp is a popular option for small tanks. This shrimp is native to Japan and is known for its ability to eat a variety of algae, including green algae, brown algae, and diatoms. The Amano Shrimp is a hardy and peaceful shrimp that will not harm other inhabitants of the tank. They are also social animals and prefer to live in schools, so it is recommended to have at least three in a tank.
Requirements
- pH: 6.0–7.0
- Temperature: 70-80 °F (21-27°C)
- Tank Size: 10 gallons and higher
- Fish Size: 2 inches
- Lifespan: 2-3 years
- Difficulty Keeping: Easy
Nerite Snails
Nerite Snails are another great option for small tanks. They are known for their ability to eat a variety of algae, including green algae, brown algae, and diatoms. This snail is native to Africa and is hardy, making it a great choice for new aquarium owners.
The Nerite Snail is a peaceful animal that will not harm other inhabitants of the tank. They are also very small and will not overpopulate the tank.
- pH: 7.0–8.0
- Temperature: 72-78 °F (22-25°C)
- Tank Size: 5 gallons and higher
- Fish Size: 1 inch
- Lifespan: 1-2 years
- Difficulty Keeping: Easy
Plecostomus
Plecostomus is a popular option for small tanks. This fish is native to South America and is known for its ability to eat a variety of algae, including green algae, brown algae, and diatoms. Plecostomus is a hardy fish that is easy to care for and will not harm other inhabitants of the tank. They are also very active and will provide a lot of movement in the tank.
When selecting algae eaters for a small tank, it is important to consider the size of the tank and the type of algae that is present. It is also important to make sure that the algae eater is compatible with the other inhabitants of the tank. It is recommended to have at least one algae eater for every 10 gallons of water in the tank.
Requirements
- pH: 6.5–7.5
- Temperature: 72-86 °F (22-30°C)
- Tank Size: 30 gallons and higher
- Fish Size: 20-24 inches
- Lifespan: 10-15 years
- Difficulty Keeping: Easy
Why Are Tanks That Are Too Small Bad For The Fish?
Fish tanks that are too small can negatively affect the health and well-being of the fish living in them. This is because a small tank cannot hold a sufficient amount of water to dilute harmful waste produced by the fish and other inhabitants. As a result, toxic levels of ammonia and nitrates can build up, leading to health problems such as disease, stress, and even death.
Additionally, small tanks limit the amount of swimming space available to the fish, which can result in stunted growth, behavioral problems, and increased aggression. Fish require a certain amount of room to swim and explore, and a small tank simply cannot provide enough space for them to live comfortably. Furthermore, small tanks are often too shallow, which means that the water does not have enough volume to properly circulate and maintain a stable temperature.
Finally, small tanks also limit the number of fish and other inhabitants that can be kept, as overstocking can quickly lead to water quality issues. Fish require a certain amount of water per fish to thrive, and adding too many fish to a small tank can result in overcrowding and further stress. A small tank can also make it difficult to provide adequate filtration, heating, and lighting, which are all crucial for the health and well-being of the fish. Overall, small tanks are not suitable for keeping fish and can result in a multitude of health and welfare issues.
FAQ
Here are some frequently asked questions that people have about the best fish for small tanks!
Can Fish Live In A 2-Gallon Tank?
The short answer is no. Some small fish such as Betta fish can survive in a 5-gallon tank, but most fish will need a larger tank as they grow and produce waste. It is generally recommended to have a minimum of 10 gallons for small fish and at least 20 gallons for larger fish species. Additionally, proper filtration, aeration, and water changes are crucial for maintaining a healthy environment for fish.
What Fish Can Live Alone In A Small Tank?
Betta fish (also known as Siamese fighting fish) are one of the few species of fish that can live alone in a small tank. Betta fish are known for their aggression towards other fish, so it’s best to keep them in a separate tank. A 5-gallon tank is suitable for a single betta fish, but a larger tank is always better to provide more swimming space and a more stable environment.
What Are The Smallest Aquarium Fish?
Here is a list of some of the smallest aquarium fish:
- Betta fish (also known as Siamese fighting fish)
- Neon tetras
- Guppies
- Endler’s livebearers
- Pygmy cories
- Dwarf gouramis
- Mosquito rasboras
- Chilli rasboras
- Cherry shrimps
It’s important to note that while these fish are small, they still need adequate space to swim and a properly maintained environment to thrive. Before adding any fish to an aquarium, it’s important to research the specific species to determine their minimum tank size requirement, diet, water parameters, and other care requirements.
Is 2 Gallons Enough For A Goldfish?
No, a 2-gallon tank is not suitable for a goldfish. Goldfish are a type of coldwater fish that can grow quite large and produce a lot of waste. They need a spacious aquarium with a minimum of 20 gallons of water and proper filtration to maintain a healthy environment. A smaller tank can lead to poor water quality, stunted growth, and other health problems for the fish.
Can Goldfish Survive In A 1-Gallon Tank?
No, a goldfish cannot survive in a 1-gallon tank. Goldfish are a type of coldwater fish that can grow quite large and produce a lot of waste, making them unsuitable for small tanks. A minimum of 20 gallons of water is recommended for a single goldfish and even larger tanks are needed if you plan on keeping multiple goldfish.
Conclusion
In conclusion, it is important to carefully research and choose the best fish for your small tank. While small fish species such as betta fish, neon tetras, guppies, and shrimps are suitable for a small tank, they still need adequate space and a properly maintained environment to thrive. It’s crucial to determine the minimum tank size requirement, water parameters, and other care requirements for each species before adding any fish to your aquarium. Keeping fish in a small tank requires responsible care and maintenance to ensure their health and well-being.
