Best fish for small aquariums


This article is written by Pet Circle veterinarian, Dr Nicole Su BSc BVMS

Small aquariums are big on fun, and provide the joy of setting up a fish tank without the hassle and commitment of a huge 100 liter tank. It is still important to ensure that you are not overstocking your tank, and that the water quality can be maintained by your filtration system. To reduce the risk of welfare issues and water fouling, a minimum of 11 liters is required, even if you are housing only one fish. Here are some types of fish and aquatic critters that are suitable for small aquariums.

Siamese fighting fish (betta)

These beautiful, unique fish are notorious for being antisocial, but they work really well in multi-species tanks! Neon tetras go well with fighting fish, as well as ghost shrimp, Corydoras, and snails. If you have a small, 11 liter tank, avoid adding other fish, and instead go with shrimp and snails. Ensure that there are plants and furniture in the aquarium to provide shelter, and to break up the line of sight.

Note: It's a common myth that siamese fighting fish should be kept in small tanks. If you're looking for a tank for your Siamese fighting fish, it's best to ignore the size of the tank you may have bought your fish in at the pet store - for a single betta, you need at least a 11 litre aquarium (but ideally 20 litres!) for them to be happy.

Zebra danio

Zebra danios are cute little fish with their pajama stripes, and are excellent additions to a small tank. These hardy little fish do well in small tanks as long as they have plenty of vegetation and furniture to hide in. They also tolerate a wide range of temperatures and pH. 


These little fish come in lots of different varieties and mutations, and are easy to feed and maintain. They are livebearers, so keep that in mind as you may accumulate more platies as time goes on! For multi-species tanks, it is best to stay away from long-tailed platies as they may get their tails nibbled. 

Glass/ghost shrimp

These adorable tiny shrimp are not only great to look at, but also help to keep the tank clean by eating any detritus, algae, and leftover food! They’re even better than low maintenance - they help with maintenance! When housed with fish, ensure that they have lots of nooks and crannies on the aquarium bottom to hide in. 

Malaysian trumpet snails

Credit: Snek01

These hardy little snails can be prolific in aquariums, and so they require monitoring to ensure that they don’t overrun the tank. They are prolific due to a very cool method of reproduction: parthenogenesis. They’re a great option for a snail that is less likely to damage aquarium plants as they feed primarily on algae. 

Cherry shrimp

These striking little shrimp can be more challenging to keep than ghost shrimp, but are supremely rewarding due to their vibrant colors. Like other small freshwater shrimp, they can be beneficial in tank maintenance by eating algae and other detritus, but they will also require supplementary feeding with algae wafers. 

Nerite snails

These beautiful snails come in a wide range of colours and shell patterns, and there’s even a variety of nerite snail with a horned shell! They are a low maintenance species and are great little algae eaters. They can also live up to two years, and are peaceful critters that get along well with other tank mates. 

Further Reading

Want to read more? Check out our other articles:

The Beginner's Guide to Setting up a Fish Tank

How to Choose the Best Food for Your Fish

Shop All Fish Supplies Now