How many fish can be in a 10-gallon tank?

In this article, we will answer the question “How many fish can be in a 10-gallon tank?” and also know the best fish species to keep in a 10-gallon tank and some of their tank specificities.

How many fish can be in a 10-gallon tank?

It is possible to keep a maximum of 9-10 small fish in a 10-gallon tank. The same rule we cited in the article “How many fish can be in a 5-gallon tank?” applies to the 10-gallon tank: “one inch of fish per gallon of water”. Always highlighting the importance of considering the species behaviour and biology. This rule only refers to smaller sized fish as bigger fish would have very limited space to swim around even if alone in the 10-gallon tank.

How to choose which fish can be in a 10-gallon tank?

To decide which fish species can be in your 10-gallon tank your need to take into account the fish species natural behaviours, such as temperament and social needs. 

More aggressive species are recommended to be kept in a lower number than the more sociable schooling fish species. However, you must also pay attention to the schooling behaviours. Animals that tend to be in bigger schools (bigger than 10 individuals) must be avoided, as the tank would become crowded or the animals depressed.

What fish species can be in a 10-gallon tank?

Some of the best choices for a 10-gallon tank and their requirements are below.

Celestial Pearl Danio (Celestichthys margaritatus)

The Celestial Pearl Danio, scientifically known as Celestichthys margaritatus, is a low-effort to maintain fish species. They are quite new to the aquarium hobby. They can grow only to one inch and they are very peaceful. Thus, they are a perfect addition to a 10-gallon tank.

They have bright beautiful colours, which make them very popular among aquarists. They prefer tanks with plenty of plants, caves, and hiding spots. Their schools have a minimum of 5 individuals and it is possible to keep up to 10 of these Danios in your 10-gallon tank.

If you opt to have 10 individuals in your 10-gallon tank, consider having only this species. However, if you decide to have less than 10 individuals, some Cherry Shrimp can make great tank mates for your fish.

Neon Tetras (Paracheirodon innesi)

Neon Tetras are very common freshwater tank fish. They are also low-effort to maintain fish, similar to the Celestial Pearl Danios. They have very bright neon colours, which give them the Neon Tetras common name. 

They prefer spaces with plenty of plants and hiding spots resembling their natural habitat, the South American streams. As they can grow only up to around 1.25 inches and are also very peaceful, it is possible to keep up to 10 Neon Tetras in a 10-gallon tank. 

Pygmy Corydoras (Corydoras pygmaeus)

The Pygmy Corydoras, scientifically known as Corydoras pygmaeus is a very tiny catfish species. They are very peaceful fish and should be kept in small schools of around 8-10 individuals. Similarly to the Neon Tetras, the Pygmy Corydoras also need plenty of hiding spots and vegetation.

A sandy substrate can favour your Pygmy Corydoras welfare, as they can also use the substrate as protection. This species can be kept in schools of up to 10 individuals if the only species in the tank. However, they are also possible to be kept with other small species, such as Ember Tetras or Rasboras.

The Pygmy Corydoras are very sensible to nitrate. Thus, keeping the water quality may require a bit more attention in comparison to the other fish on this list.

Guppies (Poecilia reticulata)

Guppies are a great choice for beginner aquarists. They are low-effort to maintain and take care of. If you opt for having Guppies in your 10-gallon tank, make sure to have only one gender school, as they can breed quite easily and overcrowd your tank with hatchlings.

If you are planning to have a breeding tank, consider the male-female ratio of 1:2. Some Java Moss and Java Fern make the tank ideal for your Guppies. It is possible to keep up to 10 Guppies in a 10-gallon tank.  

Betta Fish (Betta splendens)

Betta fish or Betta splendens are also very popular choices for freshwater small tanks. They have very beautiful colours and designs and can come in many different colours. 

Betta fish are very territorial and should be kept as the only individual of the species in a tank. If chosen carefully, some species can be good tank mates for the Betta fish. Snails and Shrimps are good choices as tank mates. In the case you consider to have other fish species with your Betta, consider having the ones that do not look similar to a Betta individual, with long flowing fins.

It is highly recommended to keep your Betta fish in a planted tank with plenty of hiding spots.

Dwarf Gourami (Colisa lalia)

The Colisa lalia is popularly known as Dwarf Gourami. They are very peaceful fish that requires intermediate effort to maintain. This species is recommended to intermediate aquarists, with previous experience.

As they can grow up to 4.5 inches, it is possible to keep up to 3 Dwarf Gourami in a 10-gallon tank. However, as they are very peaceful fish, it is possible to keep one Dwarf Gourami with a small school (5 individuals) of tiny peaceful fish, such as the Neon Tetras.

Common Molly (Poecilia sphenops)

The Common Molly is also quite low-effort to maintain. Similarly to the Dwarf Gourami, they can grow up to 4.5 inches. Thus, it is possible to keep Molly in small groups of up to 4-5 individuals in a 10-gallon tank.

Least Killifish (Heterandria formosa)

To keep the Least Killifish is an ideal fish for a 10-gallon tank. They are ideal to keep in communities with shrimp and snails. Due to their reduced size (0.8 to 1.4 inches), it is possible to keep up to 15 Least Killifish in a 10-gallon tank.

They are also very active swimmers. Thus, having structures and plants that make the tank environment more complex may provide the ideal condition for this species.

Dwarf Pencilfish (Nannostomus beckfordi)

This species is also very tiny, they can grow up to 1.5 inches. The Dwarf Pencilfish is also a good choice for beginner aquarists, and do not require too much experience to be kept. Due to their temperament and size, it is possible to keep 5-8 Dwarf Pencilfish in your 10-gallon tank.

Zebra Danios (Danio rerio)

The Zebra Danios are very beautiful zebra-striped peaceful fish. They are also low-effort to maintain and are good for beginners. As they are very peaceful fish, they can be considered to be kept in a healthy community 10-gallon tank. 

This species also prefers tanks with plenty of plants and décor providing good hiding spots. It is possible to keep from 5 to 8 Zebra Danios in your 10-gallon tank.

What are the top 5 best combinations for a 10-gallon tank?

1.   1 Male Betta and 5-10 Cherry Shrimp;

2.   5 Neon Tetras and 1 Female Betta;

3.   10 Least Killifish and 5-10 Cherry Shrimp;

4.   6 Mollies and 5-10 Ghost Shrimp;

5.   6 Mollies and 1-2 Nerite Snails;

Tips for a 10-gallon tank

–       To keep your tank water quality in good conditions to keep your fish healthy, it is extremely important to have a water change routine. Ammonia and nitrites levels are known to raise very fast in small containers;

–       Always keep a filter to maintain the water quality;

–       Do not overfeed the fish in the tank and also do not overpopulate your tank. Otherwise, contaminant levels can injury and even cause your fish death;

–       Understand your fish choices needs, their behaviour and social requirements;

–       Keep in mind that some décor and substrate will reduce your tank water capacity. Thus, recalculating the very popular “one inch of fish per gallon” rule might be necessary.

Conclusion 

In this article, we answered the question “How many fish can be in a 10-gallon tank?” and knew the best fish species to be kept in a 10-gallon tank and some of their tank specificities.

If you have any thoughts or doubts, feel free to drop us in a comment below!

Frequently Asked Questions (FAQs): How many fish can be in a 10-gallon tank?

What can I put in a 10-gallon tank besides fish?

It is possible to keep Cherry and Ghost shrimps, Snails, Java Fern and Java Moss plants, and Anubias are some examples of other organisms that is possible to keep in your 10-gallon tank. 

How often should I clean my 10-gallon fish tank?

Having a cleaning routine is essential to keep your fish tank healthy. Thus, it is needed to have a filter and keep the water parameters. In addition, you will need to make some water changes weekly or bi-weekly.

Can an Angelfish be kept in a 10-gallon tank? 

No, the Angelfish gets too big to be kept in a 10-gallon tank. 

How many fin tetras can you have in a 10-gallon tank?

As the Fin Tetras only grow to up 2.5 inches in adulthood, it is possible to keep up to 5 individuals in a 10-gallon tank. 

Can I put 2 female Bettas in a 10-gallon tank?

Yes. Female Bettas are known to live in small schools (up to 5 females). Thus, it is possible to keep 2 female Bettas in the same tank. However, it is always important to observe your fish behaviour. Sometimes even females can get a bit aggressive towards others. 

How many Cory catfish can be in a 10-gallon tank?

It depends on the Cory catfish species you are considering. It is possible to keep between 8 and 10 individuals of Pygmy Corydoras. However, if you consider bigger cory species that grow up to 4 inches, only 2 cory catfish would it in a 10-gallon tank.

References 

7 Freshwater Fish That Are Perfect for a 10-Gallon Tank. 2018. https://www.petmd.com/fish/care/7-freshwater-fish-are-perfect-10-gallon-tank

Clifford, J. Best Fish For A 10-Gallon Tank And How Many Can You Fit. 2021.https://www.tankarium.com/best-fish-for-a-10-gallon-tank-and-how-many-can-you-fit/

Dockett, E. 10 Best Fish for a 10-Gallon Tank Setup. 2021. https://pethelpful.com/fish-aquariums/Best-Fish-for-10-Gallon-Tank

Stanton, L. 22 Best Fish for a 10-Gallon Tank (and How Many can You Fit?). 2021. https://www.itsafishthing.com/best-fish-for-ten-gallon-tank/