Best nano aquarium tank with neon tetras

Best Nano Aquarium (Reviews & Buyer’s Guide)

Nano tanks are becoming more and more popular because they take up minimal space, make keeping a tank significantly cheaper and more manageable, and still add plenty of beauty and intrigue to your home’s decor. Finding the best nano aquarium for your situation is the key to success.

There are many options for nano tanks available out there, but not all are created equal. Even worse, many nano tanks are minimalist and don’t include everything you need to maintain a healthy tank, especially given the small size. Our favorite nano tank is the Fluval Sea Flex Saltwater Aquarium Kit.

We’ve tested out many different nano aquariums. Our reviews and buyer’s guide below will help you choose one that fits into your budget and provides the best aquarist experience possible.

Best Nano Aquarium Options:

What is the Best Nano Aquarium?

Our all-around favorite saltwater nano aquarium is the Fluval Sea Flex Saltwater Aquarium Kit. It has a stunning bowed front to add beauty to any room, and it includes everything you need to get started keeping a nano tank.

Our top pick for a freshwater nano tank is the 3-gallon Marineland Contour Aquarium Kit. It’s a nice, small size for an intro to freshwater tank keeping, and the heavy flow from the filter is ideal for keeping everything healthy inside your tank.

What is a Nano Aquarium?

A nano aquarium is essentially a small tank. There are very few parameters that make a tank qualify as a “nano aquarium,” so the answer to this question is somewhat subjective.

Most aquarists consider tanks under 10 gallons nano tanks, but some believe anything under 30 gallons or any tanks that can sit on tabletops or countertops should get that designation.

Generally speaking, nano aquariums include all of the accessories and devices an aquarist needs to set up their tank, aside from fish, substrate, and decorations. They typically include the actual tank, lighting, a heater (if required), and a filter with filter media.

Advantages of Nano Fish Tanks

There are numerous benefits to buying and keeping a nano aquarium. We’ll discuss the most compelling advantages below.


One of the most compelling reasons to buy a nano aquarium is the cost. As with most things, fish tanks tend to get more expensive as they get larger. This includes both the upfront cost and the price of upkeep.

Larger tanks require more material to hold larger volumes and sturdier material to stand up to the immense pressure of the water inside. The tank itself will therefore be more costly. All of the accessories, including the filtration system, heating elements, and lights, will also need to be larger and will cost more as a result as well.

Nano tanks are tiny, use significantly less material and smaller accessories, and cost much less.

In addition to your upfront cost, the price of running lights, a small filter, and a heater in a nano tank will be nearly negligible, while massive tanks can run into the hundreds of dollars a month to heat, illuminate, and keep clean.

Consumes Less Time

It should go without saying that cleaning and performing water changes on a 5-gallon tank will be significantly more manageable than doing the same maintenance on a 120-gallon tank.

A nano tank will have minimal substrate that needs vacuuming, fewer plants and less glass to remove algae from, and an overall smaller accumulation of fish waste and leftover food particles. 

You’ll be able to clean a nano tank in under twenty minutes in most cases, while a significantly larger tank could take multiple hours.

Take Up Less Space

Nano tanks are typically 10 gallons or smaller, which means they take up minimal space in your home while still adding plenty of beauty. They tend not to require their own stands, and they can often be placed on existing surfaces like countertops or tables. They’re great for those who enjoy keeping fish tanks but don’t want their home to be full of equipment. You can often get equipment specifically designed for nano tanks – such as nano skimmers – to further reduce equipment bulk.

Suitable for Beginners

Maintaining a fish tank is not only challenging, but it can also be a stressful and overwhelming experience. Small tanks offer beginner aquarists the opportunity to start small and get accustomed to the hobby before investing more money and time in a larger and more complicated setup.

Additionally, nano tanks typically include everything you need to set up your tank and begin keeping fish, plants, invertebrates, or some combination of the three.

It can be a very daunting task for a beginner to choose from the hundreds of options for heaters, filters, lighting equipment, and tanks. Opting for a nano tank means you’ll have to do minimal research on the setup before you get started. This offers beginners the opportunity to learn as they go and upgrade their equipment as their time, budget, and interest allow.

Disadvantages of Nano Fish Tanks

Nano tanks offer an easy and affordable introduction to aquarium keeping, and they’re great for beginners. However, there are some downsides to maintaining a nano aquarium.


Purchasing, setting up, and cleaning your nano tank will generally be more straightforward than with a larger tank. However, the smaller the aquarium, the more rapidly harmful chemicals will build up in the water.

The health of every aquarium relies on the nitrogen cycle, which involves beneficial bacteria consuming ammonia and nitrogen from fish waste and leftover food particles and turning them into nitrites and eventually nitrates. Although nitrates are far safer for fish and other animals than ammonia and nitrites, nitrate spikes can still kill any living organism in your tank.

A nitrate spike will occur more readily in smaller tanks because of the minimal volume, so you’ll need to monitor your nano aquarium more closely and carry out water changes more often.

Additionally, you’ll have to keep a close eye on your water temperature. Malfunctions with your heater will rapidly cause the water temp to fluctuate. In a larger tank, a heater issue would take far longer to become dangerous.

Limited Livestock Options

It should go without saying that smaller nano tanks will only be suitable for very small fish. Some individuals believe fish like Bettas can live in tanks less than a gallon, but even fish this small require at least a 5-gallon tank. The smaller the aquarium, the fewer options you’ll have for what animals you place in the tank.

Additionally, it’s easier to overcrowd a nano tank than it is a larger one. You’ll not only be limited in what types of fish and invertebrates you place in your nano aquarium but also how many.

How to Choose the Best Nano Aquarium

Choosing a nano aquarium can be challenging, and you’ll want to consider the below factors carefully when deciding.


The first and most important thing to consider when buying a nano aquarium is the size of the tank.

Best nano aquarium with neon tetras and plants

Remember, smaller tanks are inherently more challenging to keep. If you’re a beginner, it’s best to opt for a tank that’s at least 20 gallons. Tanks smaller than this might cause some frustration and stress if you don’t know how to monitor and maintain water quality and levels of ammonia, nitrites, and nitrates.

If you have some experience maintaining aquariums, feel free to choose a tank that is 5 gallons or even less. These will test your abilities as an aquarist and can provide an entertaining way to get more experienced within the hobby.

Tank Material

Next, you should consider the material of the tank itself. There are two primary options: glass and acrylic. Both have their pros and cons.

Glass Nano Aquariums

When it comes to aquariums under 20 gallons, glass options tend to be significantly cheaper. Nano aquariums made of glass will often be half the price of acrylic options or even less. If you’re looking to get into the hobby on a budget, a glass tank is likely best for you.

Glass is also more challenging to scratch than acrylic. Glass aquariums are at risk of shattering and will break more easily than plastic, but scratching a glass tank is more or less unheard of.

Glass maintains clarity over time and won’t become yellowed by chemicals in the water or algae. As such, you’ll have a clearer view of your fish and plants for as long as your glass tank is set up.

Glass tanks are also more popular, so you’ll likely have no trouble finding one in the size that you want.

With all of that being said, there are some downsides to glass aquariums. First, they’re challenging and expensive to fix if they do get damaged.

Glass tanks are significantly heavier than acrylic tanks. Depending on the size, you might have some difficulty moving your aquarium into your home or relocating it to another area.

Glass tanks might be easier to find in different sizes, but you’ll be more or less restricted to a rectangular prism shape with relatively flat walls. Acrylic options can include curved walls and seamless options; these are available in glass as well, but they’ll be prohibitively expensive for most aquarists.

Acrylic Nano Aquariums

Acrylic aquariums are becoming more and more popular because of the design options available. Curved or bowed tank walls are common in plastic tanks, and they can look very striking. Unique tank designs are easier to make with acrylic, so you’ll have more choices when it comes to shape than you would with glass options.

Acrylic is much lighter than glass, but it’s also much harder to break than glass.

However, acrylic tanks are easier to scratch, so you might need more frequent repair.

Acrylic can yellow or become hazy over time when exposed to tank water and chemicals in the aquarium. As such, plastic options might require more frequent cleaning or buffing.

Acrylic nano aquariums are often much more expensive than glass nano tanks. You can expect to pay more for a plastic tank.

There are more options for shape when it comes to acrylic, but this also means that finding accessories to fit your tank might be more challenging.


The shape of your aquarium is mostly important for aesthetic reasons. If you’re placing it on a small end table, a deep tank will likely look better. A large table might be better suited for a long or wide aquarium.

In some instances, you should consider the type of fish you plan to keep in your tank, as this may influence what shape you need. For example, angelfish and discus are both better suited for tall tanks.


Finally, you should consider what accessories are included with your tank. If you’re purchasing a nano tank as a beginner, chances are you want one that is ready to set up straight from the box. Even if you’re an experienced aquarist, it’s nice to get everything you need for a smaller tank with a single purchase.

Many nano tanks include heaters and filters designed for smaller volumes and are made specifically for the shape and size aquarium you buy. Some even include substrate and decorations that fit perfectly inside the tank, which can save you money and time when setting up your aquarium.

What Are the Ideal Fish for Nano Aquariums?

Nano aquariums are best for smaller fish that don’t necessarily need a lot of room to swim around. Most nano tank keepers opt for the below species:

  • Harlequin or Chili Rasbora
  • Least Killifish
  • Dwarf Suckers (also known as Otocinclus)
  • Scarlet Badis
  • Small Tetra species (like Neon Tetra and Ember Tetra)
  • Bettas
  • Guppies
  • Dwarf Cichlids
  • Danio
  • Minnows
  • Gourami

These fish species are all tiny and can do well in tanks around 5 gallons (and, in some cases, even less).

Best Nano Aquarium Options

We’ve tested many different nano aquariums. We’ll list our favorites below and then offer some insight into what we like and dislike about each.

Fluval Flex Aquarium 34L, 9gal

This nano aquarium is a bit expensive, but it offers a beautiful appearance with a striking bowed front. Surprisingly, this is a glass aquarium, so it will resist scratches well and always appear clear.

This kit includes everything you need to get set up, including a heater, filter, and customizable light.

One of our favorite things about this nano tank is that all of the equipment is hidden behind the rear wall for a sleek appearance.


  • The rear compartment hides all of the equipment
  • The included LED light is bright and multi-colored


  • It includes everything you need to get started
  • It’s made of durable glass that resists scratching


  • It’s a bit expensive
  • Finding other accessories to fit the shape might be challenging

Marineland Contour Aquarium Kit, 3 Gallons, Rounded Glass Corners

This glass aquarium will resist scratching, and it’s durable enough to stand up to years of use. The rounded front edges make for a beautiful appearance and striking design.

This kit includes a powerful light and a three-stage filter. However, it doesn’t come with a heater, so you’ll need to buy one separately if required.

This nano aquarium is ideal for saltwater setups, as the filter is powerful and creates the flow rate that tropical fish tend to prefer.


  • The bowed glass is beautiful and aesthetically pleasing
  • The rear compartment will help hide your equipment for a seamless appearance 


  • It includes a filter and LED light
  • The filter’s flow rate makes it suitable for saltwater setups
  • It’s very affordable


  • It doesn’t include a heater
  • It might be challenging to find accessories that fit the shape and dimensions

Fluval SPEC Aquarium Kit, Aquarium with LED Lighting and 3-Stage Filtration System, 5-Gallon

This glass nano aquarium has rounded edges for a beautiful appearance. It’s slim and deep, so it might not fit nicely in your home, depending on where you place it.

This kit includes a filter and an LED light, but it doesn’t come with a heater. You’ll need to buy one separately if you need to heat your water.

The filter is hidden behind a sleek wall, but its placement on the side of the tank is a bit awkward, depending on where you display your aquarium.


  • It has rounded edges for a beautiful appearance
  • It is deep enough for angelfish, discus, and other fish that prefer deep tanks


  • It includes a filter and LED light
  • The included wall hides the filter for a sleek appearance


  • The wall that blocks the filter is awkwardly placed for some setups
  • It’s somewhat expensive
  • It doesn’t include a heater

Marina LED Aquarium Kit, 5 Gallon

This simple glass aquarium has a rectangular prism shape. Although it’s not as striking as those with rounded edges, finding accessories for it will be very straightforward.

It includes a hang-on-back filter and an LED hood. However, there is no heater, so you might have to purchase one separately.

It’s relatively expensive for a 5-gallon tank.

The filter and any other accessories will need to hang on the back, so they might detract from your tank’s appearance.


  • It includes an LED hood
  • It comes with a powerful HOB filter


  • Accessories that fit are easy to find
  • It comes with a filter and LED hood


  • It doesn’t include a heater
  • It’s relatively expensive

Tetra LED Cube Shaped 3 Gallon Aquarium with Pedestal Base

This nano aquarium is made of acrylic, but it’s still very affordable. It has rounded edges for a stunning appearance.

It includes an LED light and a small filter that are perfect for the 3-gallon capacity. The filter sits inside the tank and takes up space, so it’s not as visually appealing as a hidden filter. It doesn’t include a heater.

This tank is shaped like a cube, so it might be challenging to find accessories to fit it. 


  • The cube shape is exciting and appealing
  • The acrylic walls are scratch-resistant


  • It includes a filter and LED light
  • The rounded edges make for a beautiful appearance
  • It’s very affordable


  • It doesn’t include a heater
  • Accessories that fit might be hard to come by

Tetra Crescent Aquarium Kit 5 Gallons, Curved-Front Tank With LEDs

This small acrylic tank has a curved front for a beautiful appearance. As striking as it is, finding accessories that fit will be very difficult.

It includes an LED light fixture and a filter. There is no heater included. The filter sits inside the tank and isn’t hidden from view once set up. Additionally, the filter is a bit loud.

Despite being acrylic, this tank is very affordable and will likely fit into most aquarists’ budgets.


  • The included filter is perfect for this size tank
  • The bowed front wall leads to a beautiful appearance


  • It includes a filter and LED light
  • It’s very affordable


  • It doesn’t include a heater
  • Finding accessories that fit can be challenging
  • The filter is a bit loud

Coralife LED Biocube Marine or Freshwater Aquarium Kit

This glass nano tank has rounded front edges, which give it a beautiful appearance. The filter and other equipment are hidden behind a wall for a clean and spacious look.

It includes a programmable LED light to keep your fish happy and at a low-stress level. It also includes a filter designed for this smaller capacity. However, there is no heater included with this aquarium.

This is exceptionally expensive, so it’s likely to be above your budget. However, the equipment is ideal for saltwater setups.


  • The rounded front edges lead to a gorgeous appearance
  • The interior wall hides all your equipment


  • It includes a filter and LED light
  • It can handle saltwater setups
  • The LED light is programmable


  • It’s costly
  • It doesn’t include a heater

Best Nano Aquarium FAQs 

What is considered a nano tank?

“Nano tank” can refer to anything smaller than 30 gallons. However, most aquarists refer to tanks that are 10 gallons or smaller as “nano” setups.

Are Nano Tanks hard to keep?

Nano tanks are a bit more challenging to maintain than larger ones. This is due to the higher risk of ammonia and nitrite spikes.

How do you maintain a nano aquarium?

A good, three-step filter and routine water changes will suffice to maintain most nano tanks. However, you’ll also likely want to invest in a reliable water testing kit to ensure your levels are within the acceptable ranges.

How many fish can be in a nano tank?

The answer to this question depends on the size of the tank and the species of fish. Nano tanks that are less than 10 gallons tend to be best with one or two small fish or three to four tiny fish. Larger nano tanks up to 30 gallons can accommodate a small school of fish, depending on the species’ size.

How do you start a nano tank?

Starting a nano tank requires about six to eight weeks of “cycling,” which involves adding some fish food and letting your filter run continuously without any fish inside. This will help develop the beneficial bacteria in your filter cartridges that will keep the water clean and healthy.

Do nano tanks need skimmers?

A skimmer or hearty filter is required for nano tanks, especially because harmful compounds can build up rapidly in such small volumes.

What equipment do I need for a nano reef tank?

For a successful nano reef tank, you’ll need a heater, a powerful filter with a heavy flow rate, a thermometer, a refractometer for testing salt content, and a good water quality testing kit.

How much flow does a nano reef tank need?

Reef tanks require a higher flow rate than standard tanks. You’ll want a filter that can accommodate a total turnover about 15 times per hour. For a 5-gallon reef tank, a filter with a flow rate of around 75 GPH should be sufficient.

How do you cycle a nano reef tank?

The process to cycle a nano reef tank is the same as with a larger one. Add some fish food each day while your filter is running. Do this for about six to eight weeks or until your tests reveal minimal levels of ammonia and nitrites in your water.

Conclusion: Best Nano Aquarium Options

Nano tanks are a fun and affordable way to get into the hobby of aquarium keeping. They take up minimal space inside your home but still provide plenty of beauty and entertainment. The best part is, most nano aquariums come with filters and LED lights, so you can get started right away without having to do extensive research on equipment.

Our favorite nano tank for saltwater setups is the Fluval Sea Flex Saltwater Aquarium Kit. It offers a stunning curved display for your tank, and it comes with everything you need to get started quickly.

If you’re looking to start a freshwater nano tank, we recommend the Marineland Contour Aquarium Kit. This kit has an ideal filter for reef tanks that need a heavier flow rate, plus it includes all of the equipment you’ll need to set up your tank right away.

Leave a Comment

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.