The best nano aquariums offer a balance between enough room to support your fish and being small enough to keep in a compact space like the corner of your desk.
We spent weeks researching and testing some of the latest tanks to help you find the best one for your needs.
And overall we crowned the Fluval Spec V as the best nano aquarium!
But everyone’s needs are different, that’s why we’ve included reviews of the best brands for every category of nano aquarium. So let’s get started!
- Best Overall: Fluval Spec V
- Best For Value: Marineland Portrait
- Premium Pick: Hygger Horizon 8 Gallon
- Best Starter Kit: GloFish 5 Gallon Portrait
- Best for Saltwater: Fluval Sea Evo V
- Best Acrylic Tank: Tetra LED Cube
- Best Curved Glass: MarineLand Contour Glass
- Best Cylindrical Tank: Koller Products AquaView 3 Gallon
- Best Fishbowl: biOrb 4 Gallon Classic
9 Best Nano Aquarium Picks Reviewed
All the nano aquariums on this list are compact and small enough to keep on a desk, small cabinet, or kitchen work surface. Many come in different volume sizes you can choose from too!
1. Fluval SPEC V Freshwater Aquarium Kit
Photo: Chewy.com
- Shape and Capacity: Rectangular, 5 US gallons
- Dimensions and Weight: 20.5 (l) x 7.5 (d) x 11.6 (h) inches, 11.02 pounds
- Material: Glass
- Equipment Included: 37 LED lighting system, hidden 3 stage adjustable filter (55 to 80 GPH), aquarium canopy with access slot
- Best for: Overall
The Fluval SPEC V nano aquarium is a stylish and modern-looking tank offering fantastic value considering the excellent build quality. Its long, narrow design gives your fish more horizontal swimming space which many species prefer. And it’s small enough to comfortably fit on your desk at home or in the office.
The 3 stage filtration unit, consisting of a foam block, activated carbon, and BioMax rings, is cleverly hidden in the side panel and will keep your water crystal clear. And although the adjustable pump is powerful it is incredibly quiet, making the tank ideal for your bedroom.
Fluval includes a 7000k 37 LED lighting unit which is plenty bright enough if you want to grow live plants.
2. Marineland Portrait Glass LED Aquarium Kit
Photo: Chewy.com
- Shape and Capacity: Rectangular (portrait), 5 US gallons
- Dimensions and Weight: 11.81 (w) x 11.62 (d) x 17.05 (h) inches, 12.0 pounds
- Material: Glass
- Equipment Included: Hidden filter and pump, LED lighting with white day and blue moonlight settings
- Best for: Value
Marineland’s ML90609 nano aquarium has a surface area of 11.81 x 11.62 inches. This provides plenty of area for oxygen exchange for your fish. And the portrait style means you can easily fit it on a smaller desk or cabinet.
It has a 3 stage hidden filtration system which is very quiet when running. Its flow rate is adjustable down to 35 Gallons Per Hour (GPH), making it perfect if you want to keep fish with delicate fins.
The 9 white LED lights are very bright and will sustain a variety of low-level plants. And you can use the 6 blue moonlight LEDs in the evening if you don’t want it so bright.
3. Hygger Horizon 8 Gallon LED Glass Aquarium Kit
Photo: Amazon.com
- Shape and Capacity: Rectangular with wide curved front, 8 US gallons
- Dimensions and Weight: 19.0 (w) x 11.89 (d) x 9.6 (h) inches, 68.0 pounds
- Material: Glass
- Equipment Included: 7 watt 110 GPH internal power filter, adjustable 3 mode LED lighting, 3D rockery mountain background, non-slip cushion pad
- Best for: Premium pick
As well as being attractive, the curved front of this Hygger tank means the base is bigger at 224.2 square inches. So you could comfortably keep around 5 or 6 fancy guppies or rasboras. A further stylish feature is the 3D rockery background. But do be aware, this is glued to the back and can’t be removed.
The strip LED light has a white mode, red and blue, or red, white, and blue setting. You can also change the brightness from 100% down to 10%, making it perfect for daytime and evening use.
Hygger’s 2 stage internal filter is fully adjustable but at 110 GPH it’s powerful too and will keep your water crystal clear. Some people do report the filter can suck up small fish though, and Hygger also recommends you are careful. So use a filter guard or filter sponge over the intake to prevent any accidents.
4. GloFish 5 Gallon Portrait Aquarium Kit
Photo: Chewy.com
- Shape and Capacity: Rectangular (portrait), 5 US gallons
- Dimensions and Weight: 11.0 (w) x 11.0 (d) x 16.25 (h) inches, 15.0 pounds
- Material: Glass
- Equipment Included: Hidden filter and adjustable pump, GloFish LED lighting with 4 settings (sunlight, moonlight, midnight, twilight)
- Best for: Starter kit
GloFish offers these tanks in a range of sizes from 3 to 20 gallons. But we think the 5-gallon option is a great starter kit. The portrait style is perfect for comfortably keeping 4 or 5 GloFish tetra or similar species, whilst being small enough to fit nicely on your desk.
GloFish are bred to fluoresce, and the LED lighting in this tank is designed to emphasize that. It features blue LEDs that emit slightly more UV light, and if you plan to keep GloFish you’ll find they do glow more brightly.
The hidden 3 stage filtration system is adjustable but I would advise you to baffle the nozzle with filter sponge to further reduce the flow if you keep fish with delicate fins.
5. Fluval Sea Evo V Saltwater Fish Tank
Photo: Amazon.com
- Shape and Capacity: Rectangular, 5 US gallons
- Dimensions and Weight: 24.5 (w) x 11.8 (d) x 16.3 (h) inches, 11.0 pounds
- Material: Glass
- Equipment Included: Hidden 3 stage filter and adjustable pump (55 to 80 GPH), 11,000k 37 LED lighting with day and night settings, aquarium canopy with access slot
- Best for: Saltwater
The Fluval Sea Evo V is a close cousin of the Fluval SPEC V, but with some key differences specifically for its use as a saltwater nano aquarium. Firstly, it’s bigger – with over 2928 cubic inches of extra space. This is perfect if you are keeping saltwater fish as typically you can’t keep as many as you would in a freshwater tank.
But the 24.5 x 11.8-inch base should still allow you to place it on a desk or small cabinet if you are constrained for space.
The Sea Evo V also has a more powerful 11,000k lighting system meaning you can keep medium light corals and live rock comfortably.
The 3 stage filter is capable of cleaning the bio-load associated with saltwater tanks. This is especially important in a nano aquarium where waste can build up quickly.
Overall this tank is held in high regard with excellent reviewer feedback on its sleek design, and ability to safely support mushrooms, corals, and other marine life.
6. Tetra LED Cube Shaped 3 Gallon Aquarium
Photo: Chewy.com
- Shape and Capacity: Cube, 3 US gallons
- Dimensions and Weight: 10.32 (w) x 11.95 (d) x 17.5 (h) inches, 4.4 pounds
- Material: Acrylic
- Equipment Included: Tetra 3i Whisper Power filter, pedestal base, LED light
- Best for: Acrylic nano aquarium
This 3 gallon cubic nano aquarium from Tetra strikes a great balance between good air to water surface ratio and being compact enough to fit on a small desk or cabinet. As it’s a 3-gallon tank, you should only use it to keep 2 or 3 nano fish maximum.
The Whisper power filter is relatively quiet and can be adjusted to reduce the flow for fish that need a low flow tank.
Overall it’s a very affordable little nano aquarium, made of shatter-resistant plastic, and would make a great starter tank for a kids bedroom. Many people bought this tank to keep a single betta and report that it makes an excellent and affordable home!
7. Marineland Contour Glass Aquarium
Photo: Amazon.com
- Shape and Capacity: Cube, 3 US gallons
- Dimensions and Weight: 11.82 (w) x 11.62 (d) x 12.05 (h) inches, 10.5 pounds
- Material: Glass
- Equipment Included: Sliding canopy, hinged rail with white LEDs for daylight and blue for moonlight setting, hidden 3-stage MarineLand filter with adjustable pump
- Best for: Rounded glass nano aquarium
An alternative to the Tetra LED Cube, the 3 gallon Marineland Contour is a similar but smaller version of the ML90609. The LED lighting daylight and moonlight settings are powerful enough to support a range of low-level plants should you want to keep them.
Marineland’s integrated 3 stage filter is very quiet on its lower setting, and the output nozzle can be removed reducing the return flow to a trickle rather than a jet. This is perfect if your fish need calm water.
The activated carbon filter cartridge has a ribbed back giving more surface contact with the water. This will help minimize any nasty chemical smells coming from your tank!
8. Koller Products AquaView 3 Gallon 360 Aquarium
Photo: Chewy.com
- Shape and Capacity: Cylinder, 3 US gallons
- Dimensions and Weight: 10.25 (diameter) x 14.5 (height) inches, 1.0 pound
- Material: Acrylic
- Equipment Included: Aquarium hood with integrated LED lights in 7 colors, Koller Products hanging power filter
- Best for: Cylindrical nano aquarium
This 3 gallon nano aquarium from Koller Products is the lightest of all those featured, and its compact size means you can position it on a small desk or even a side table.
The battery-powered LED lighting in the hood can be easily cycled through 6 colors and a white light setting. It also features a continuous on, 2-hour, or 4-hour timer. Perfect for the evening when you can head off to bed and leave it to switch itself off.
As it’s a cylindrical tank, the 360-degree viewing angle makes it perfect if you want to be able to view from different positions. Especially if you have a compact space.
9. biOrb 4 Gallon Classic Aquarium
Photo: Chewy.com
- Shape and Capacity: Fishbowl/ sphere, 4 US gallons
- Dimensions and Weight: 12.87 (diameter) x 13.27 (height) inches, 6.28 pounds
- Material: Acrylic
- Equipment Included: 5-stage filtration system, lid with integrated long life LED light
- Best for: Fishbowl nano aquarium
The biOrb nano aquarium comes in an attractive fishbowl design and a range of sizes (4, 8, 16, and 28 gallons). The larger sizes make it perfect for a saltwater or freshwater tank.
We’ve featured the 4 gallon version here, which has a diameter of just under 13 inches, meaning it will fit perfectly on your desk or bedroom cabinet.
The 5 stage filter hidden in the base uses biological, mechanical, and chemical media supported by ceramic media in the form of small rocks that form the base substrate. This helps to keep your water crystal clear as long as you don’t overstock with fish. Many betta owners love this tank as the filter is gentle because it sits under the substrate.
Guide To Buying The Best Nano Aquarium
Before buying a nano aquarium, there are several things you should bear in mind.
What Is A Nano Aquarium?
A nano aquarium is simply a small fish tank. Often the type you could place on a desk in your office, or on a cabinet in the bedroom.
There is no specific definition for what size makes a nano aquarium. But while some aquarists define a nano aquarium as 30 gallons or less, most consider it to be 10 gallons or less.
What Are The Advantages Of A Nano Aquarium?
There are a number of benefits to buying a nano aquarium that could make it a good choice for you.
Cheaper To Buy And Run
Whilst some premium nano aquarium setups can cost a reasonable amount, nano aquariums are almost always cheaper than larger tanks. Especially when you include all the additional equipment required.
They are cheaper to run too. Consider heating for example. A 5 gallon nano aquarium would typically need a 25 watt heater. Running 24 hours a day, that would be 219 kWh per year [1], costing about $26.
For a larger 40 gallon tank with a 100 watt heater, this would be around 876 kWh, costing roughly $105 per year [2].
Takes Up Less Space
A nano aquarium is a great choice if you don’t have the space for a larger aquarium.
A 5 gallon cube shaped nano aquarium of around 10.5 x 10.5 x 10.5 inches is a perfect little size if you want it to sit on an office desk or small sturdy cabinet.
Takes Less Time To Maintain
Because it’s a smaller tank, you are likely to need to do water changes more frequently – around once a week.
But in a small 5 gallon nano aquarium changing 20% of the water (1 gallon) is a lot quicker and easier than doing the same for a 150 gallon tank. Where you would be changing out 30 gallons each time!
Often Come As A Complete Kit
As nano aquariums are frequently sold as starter kits, they regularly come with most of the basic equipment needed to set up a complete tank.
Many nano aquariums come with built-in filtration, which is specifically set up with the correct flow rate for that size of tank.
We would usually recommend your tank water cycles around 6 to 10 times per hour. So, for example, a 5 gallon nano aquarium sold with a 55 GPH (gallon per hour) pump will easily manage this.
Suitable Weight For Some Furniture
A nano aquarium is often small enough to fit on top of most furniture such as a desk without the need for an aquarium stand.
But when it comes to weight you should be careful. The weight of 1 US gallon of water is 8.34 lbs [3], so a 5 gallon nano tank can weigh around 41 lbs. And that’s without any substrate or decorations!
So make sure you locate your nano aquarium on a sturdy desk, cabinet, or kitchen top that can hold the weight.
What Are The Disadvantages Of A Nano Aquarium?
You’ll also want to be aware of some of the drawbacks of a nano aquarium before you buy.
Not Suitable For Many Fish Or As A Community Aquarium
If you want to keep a heavily stocked community tank, then it goes without saying that a nano aquarium is not going to be for you.
Due to their size, nano tanks are only suitable for a very small number of fish. So this may be a single fish or a small school of the same species. Either way, you are not going to be able to have a large variety.
Can Be Challenging For Beginners
I’m not saying that if you are a beginner you shouldn’t buy a nano aquarium, but what I am saying is you should be aware that it can be harder to keep.
With a small aquarium, you need to regularly check your water parameters (at least weekly) as harmful ammonia and nitrites can build up quickly.
You are also likely to need to perform maintenance and water changes more frequently.
How To Choose The Best Nano Aquarium For You
When selecting the right nano aquarium for your needs, you’ll need to consider a number of factors.
What Fish Are Suitable For Your Nano Aquarium?
You need to carefully consider what types of fish you are going to keep before buying your nano aquarium.
Cherry barbs, for example, are small fish growing to between 1.5 to 2 inches. But they are also shoaling fish and you should keep them in a group of at least six. This means you can’t keep them in a 5 gallon nano aquarium as they won’t have enough space.
A small school of rasboras, fancy guppies, or even freshwater shrimp are good choices for a nano aquarium. You could also keep a single betta in a nano aquarium with the preferred minimum size being 5 gallons.
How Many Fish Can You Keep In A Nano Aquarium?
The general rule of thumb for a freshwater aquarium is for each inch of fish there should be 1 gallon of space for them to swim.
So, for example, in a 5 gallon nano aquarium, you are going to be limited to a maximum of 5 one-inch long fish.
Does Your Nano Aquarium Come As A Complete Kit?
I’d generally recommend that you buy your nano aquarium as a complete kit.
Nano aquarium kits often come with integrated filtration and lighting which are specifically designed to fit that tank. This can be useful as nano aquariums can sometimes be unusual shapes such as curved or tapered.
It’s not essential to do this though as you can pick up equipment like a heater as needed from Amazon, Chewy, or other stores.
What Size Filter Does My Nano Aquarium Need?
If you need to buy a separate filter for your nano aquarium you’ll need one that can filter the water at least 4 times an hour. This would be a flow rate of 4 GPH (or gallons per hour).
But to keep your water parameters in check, it’s always better to buy a filter with a little more power than needed.
| Nano Aquarium Volume | Filter Flow Rate (Gallons Per Hour) |
| 3 US Gallons | 15 GPH |
| 5 US Gallons | 25 GPH |
| 10 US Gallons | 50 GPH |
You will also need to consider the type and size of the filter so that it will fit in your nano aquarium.
There are plenty of smaller hang-on-back (HOB) or internal power filters with the flow rates shown above that should easily fit in your nano aquarium. But do check the measurements before you buy.
What Size Heater Does My Nano Aquarium Need?
As your nano aquarium contains less water than a large tank, it may be obvious that it will take less power to heat.
But it’s important to note that the temperature of the room also makes a difference to the wattage you’ll need.
We’ve based the table below on keeping an aquarium in your home at a general room temperature of 72°F [4].
| Nano Aquarium Volume | To Maintain Approx. 75 to 80°F |
| 3 US Gallons | 15 watt |
| 5 US Gallons | 25 watt |
| 10 US Gallons | 50 watt |
As well as wattage, you also need to think about the physical size of your heater. As nano aquariums are that much smaller you need a heater small enough to sit correctly and be fully submerged.
Should You Choose A Glass Or Acrylic Nano Aquarium?
Both glass and acrylic are great materials for nano aquariums. But they both have their pros and cons. What you really need to do is decide which of these are most important to you.
Pros And Cons Of Glass Nano Aquariums
The first thing to note is smaller glass aquariums under 10 gallons are often much less expensive than acrylic ones. So if budget is important to you, glass may be best.
Glass aquariums also tend to be more readily available and made to industry-standard sizes. This makes things easier if you are adding additional equipment to your tank.
You will also find that glass maintains its clarity. Sun bleaching or chemicals in the water won’t cause any yellowing so you’ll have a clear view of your fish for the life of your aquarium. It’s also very difficult for glass to get scratched.
However, one of the limitations with glass is that it is twice the weight of acrylic. A 10 x 10 x 10 inch cubed nano aquarium in 3/16 inch thick tempered glass would weigh around 8.5 lbs without any water added! [5]. They are also much more difficult to repair if they do get chipped or scratched.
Pros And Cons Of Acrylic Nano Aquariums
Modern acrylic tanks offer a huge range of different design options and shapes. Curved, tapered, or bowed designs give you much more choice.
And whilst acrylic is that much lighter than glass, it is also that much harder to break. This means if you need to drill holes to add accessories you can do so quite easily.
Acrylic can yellow over time due to chemicals in the water, but it can be easily buffed and re-polished to correct this. If you buff your tank regularly you’ll find it remains very clear.
It can scratch more easily than glass, but then again is easier to repair.
Acrylic aquariums tend to cost more than glass. And whilst the range of unusual shapes is great from a design point of view, bear in mind that it can make it harder when trying to find standard accessories to fit inside.
What Shape Should Your Nano Aquarium Be?
Most importantly you need an aquarium that is going to be suitable for the type of fish you want to keep. Many species tend to prefer longer tanks rather than tall ones as there is a greater surface area available for oxygen exchange.
The issue with a long rectangular tank is if you are opting for a nano aquarium it’s likely that you’ll want to keep it in a smaller area, such as on a desk, where space may be limited. So you may want to strike a balance between length and height.
Cube or portrait nano aquariums can be an ideal compromise. You can also create ‘inhabitant zones’ to fill the space. For example, you could keep two freshwater shrimp which would stay at the bottom with 3 or 4 rasboras swimming higher up.
Overall I would recommend a rectangular or cube as the best nano aquarium shape.
Our Verdict
Choosing the best nano aquarium to meet your needs is often a balance of having enough room to support your fish, and finding a tank small enough to fit your small space.
We think the Fluval Spec V provides this balance and gives the space your fish need whilst being compact and stylish to fit in your home!
FAQs About Nano Aquariums
Here are some answers to the top frequently asked questions about nano aquariums.
What Is The Best Nano Aquarium?
After research and testing, we found that the Fluval Spec V is the overall best nano aquarium. But check out the rest of this article above for our alternatives.
Who Is A Nano Aquarium For?
Freshwater nano aquariums can be kept by any level of fish keeper, but if you are a beginner be aware you need to keep a close watch on water parameters in a smaller tank.
How Big Are Nano Aquariums?
While some aquarists consider anything under 30 gallons to be a nano aquarium, most define it as 10 gallons or less.
Are Nano Aquariums Easy To Keep?
Nano aquariums can be more challenging to keep. Ammonia and nitrites can build up quickly so testing your water at least weekly is key. Weekly water changes may be needed to keep these at the right levels.
How Many Fish Can You Have In A Nano Aquarium?
This depends on the species of fish but generally, you should allow one gallon per inch of fish.
Are Nano Aquariums For Freshwater And Saltwater?
Yes. Nano aquariums can be for both, although it is recommended more experienced aquarists keep saltwater nano aquariums as the fish can be more expensive and there is less room for error in your water parameters.
