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What Animal Can be Kept in a Tank Just Under 3 Gallons

What Animal Can be Kept in a Tank Just Under 3 Gallons

The smallest common size of tank is the three-gallon tank.

I’ve learned that there aren’t many animals that can be kept healthy in such a small tank, though some people attempt to keep fish and animals that are too large for a three-gallon tank.

Even the small animals that can be kept in a three-gallon tank need to be cared for properly to keep them healthy. 


What animal can be kept in a tank just under 3 gallons?

Snails, shrimp, and ants are the only types of animals that are commonly kept in a 3-gallon tank. Anything larger than shrimp cannot be kept humanely in a 3-gallon tank. It’s technically possible to keep some small fish in a three-gallon tank, but this fish will likely have short and unhealthy lives.



Snails in a 3-gallon tank

Aquatic snails are commonly kept in small three-gallon tanks. Keep in mind that a three-gallon tank is usually only enough for one snail.

This is okay, as snails do not need to be kept in groups like many fishes.

It’s definitely possible to keep a snail as your main pet. However, many people keep snails in tanks with shrimp.

Snails can be useful when keeping shrimp because they eat pretty much anything. This means that they will eat algae and dead plants along with surplus food.

An excessive buildup of algae or dead plants in your tank can endanger the health of your shrimp.

There are several types of snails commonly kept as pets, but the most common is the apple snail.

The apple snail is relatively large, as it can reach sizes of six inches or more. It is yellow or yellow-green in color.

There are only a few things that you need to keep in mind if you are planning on putting a snail in a three-gallon aquarium.

First, you will need a small filter to ensure optimal oxygen levels in the water for them. Second, you will need to ensure that the water is dechlorinated and has a pH of around 7.

Snails have a penchant for escaping if they have the chance, so you should ensure that there is a secure lid on your tank.

Finally, snails should be fed a mixture of fish food and vegetable matter.



Shrimp in a 3-gallon tank

Shrimp are the most interesting (in my opinion) and most popular animals kept in three-gallon tanks. The Neocardina shrimp is the type most commonly kept as a pet.

There are other types of shrimp that are occasionally kept as pets, but this is rare. Shrimp are great for small tanks because they are tiny and are not overly sensitive to water temperature or acidity.

However, they can be very sensitive to chemicals that get into the water.



Neocaridinas in a 3-gallon tank

Neocaridinas are the most popular type of pet shrimp these days. This is likely because they can be found in so many colors.

Their colors can range from blue, green, clear, and even red. Neocaridinas, commonly known as “Neos,” can be found in pretty much any pet store.

Neos should be kept at room temperature. They like water with a pH of around 7, which is the same pH that snails prefer.

This, and the fact that shrimp and snails have a symbiotic relationship, makes them great tankmates.

Neos only need to be fed two or three times a week. They’re not picky eaters, so even simply feeding them with standard fish food is enough.

It is also easy to find food specifically created for shrimp. I also keep plenty of live plants in my shrimp tank, which gives my shrimp the opportunity to snack if they wish.

Shrimp also prefer to hide in the midst of the vegetation anytime they are disturbed. You should keep around 10 shrimp in a three-gallon tank.



Ants in a 3-gallon tank

Ants are just about the only terrestrial animal that can be kept in a three-gallon tank.

A three-gallon tank is too small for other insects commonly kept as pets (e.g., a praying mantis). Many people like to keep ant farms, as they look cool and are very low-maintenance.

It is easy to keep an ant farm, but there are several best practices that you need to follow to keep the colony healthy.

Filling your tank with sand is the first step in starting an ant colony. You can use any type of sand.

Once you’ve filled up the tank, you have to get a queen ant.

It’s possible to catch or buy a queen ant. If you’re new to ant keeping, you can buy a starter colony that will likely consist of a queen ant and a few worker ants.

You can simply drop these ants into your tank and let them begin burrowing.

Ants need to be fed three times daily. You should feed them small pieces of fruit and dead crickets (which you can buy from any pet store).

Ants also need sugar water. Give your ants 7 parts water mixed with one part sugar by pouring the mixture into a bottle cap and putting it in the tank.


Frequently Asked Questions about Animals you Can Keep in a Tank Just Under 3 Gallons


Can I keep betta fish in a tank this small?

Betta fish are very popular, so many people try to keep them in small three-gallon tanks. However, these tanks are too small. The betta fish may live for a short time, but it will be sickly and will likely die soon.


Is it possible to keep frogs in a three-gallon tank?

It is not a good idea to keep even small frogs in a three-gallon tank. This is because frogs need to swim and jump around in order to stay healthy.


Keeping Animals Healthy in a Three-gallon Tank

Whether you are keeping shrimp, snails, or ants, you need to constantly provide them with fresh food and water.

You must also monitor the ambient temperature and try keeping it steady as much as possible.

Finally, you need to keep chemicals from getting into the tank.