Best 20 Gallon Fish Tanks For The Enthusiasts

20-gallon fish tanks are for enthusiasts. No faint-hearted can afford to invest in a 20-gallon fish tank. And we’re not talking about the budget here. While the budget will play a role in determining which type of fish tank to invest in, but with a 20-gallon fish tank, things are a bit different.

A 20-gallon fish tank emphasizes size. People who fancy large aquariums and see room for more fish and aquatic life, prefer to invest in a large fish tank, specifically a 20-gallon one.

However, if you do plan on getting one for yourself, you need to be committed enough to maintain it in the long run. Motivation won’t just cut it; you should be responsible and value commitment with a 20-gallon fish tank because you’ll end up cleaning and maintaining it more often.

How Big Exactly is a 20-gallon Fish Tank?

While different fish tanks come in different sizes, one thing you need to take note of, is not to confuse the 20-gallon marking with the overall size of the aquarium or fish tank you’re investing in, instead, you should specifically go through the dimensions of fish tanks, as the manufacturer may add more bezels, or incorporate a smaller form factor, resulting in compact design language or dimensions.

However, when it comes to the marking or advertisement of a 20-gallon fish tank, manufacturers are talking more about the internal space or capacity, specifically of the water. This means that any advertised 20-gallon fish tank will have 20 gallons of internal water space to accommodate your fish and other accessories that you want to rock your fish tank with.

Now, talking about the overall size. In general, a 20-gallon fish tank will have dimensions that comprise 12-inch width, 30 inches length, and 12-inch height.

How Much Does a 20-gallon Fish Tank Weigh?

While an average 20-gallon fish tanks have dimensions of 30” by 12” by 12”, the weight is exclusively determined by the make or material of the aquarium used.

Materials like glass or iron will weigh more, ranging between 200 to 250 pounds, while materials like plastic or acrylic will weigh much less, coming under 150 pounds.

You will also need to look at the housing or frame of the aquarium. If the frame of the 20-gallon fish tank is made from iron, then the weight will be on the higher or heavier side. At the same time, if the frame is made up of aluminum, then the fish tank would be lighter, in terms of overall weight.

Hence, there’s no set weight for a 20-gallon fish tank, as it depends on the materials of the fish tank that the manufacturer has used to build it.

How Many Fish Can a 20-gallon Fish Tank Hold?

As we mentioned at the start, 20-gallon fish tanks are bought to be equipped with more fishes making up large and beautiful aquatic life.

Since 20 gallons is ample space, you have a lot more room to fit multiple fish.

However, when it comes to the exact number of fish, you need to take note of its associated rule of thumb, which is that for general fish, you can keep or add one fish per gallon, meaning that you can store 20 fish inside a 20-gallon fish tank.

However, speaking specifically, in terms of fish size, then you can store 15, one-inch sized fishes inside a 20-gallon fish tank and up to 6 2.5-inch fish. Here, you need to decide which fish and how many you’d like to store in your 20-gallon fish tank.

Is a 20-gallon Fish Tank Sufficient?

20-gallon fish tanks are designed in such a way that they will not take up a significant amount of space in your living room, but at the same time, a 20-gallon fish tank won’t be cumbersome and would serve as the right and optimal size enough to house many fishes at the same time, making 20-gallon fish tanks one of the most popular home aquarium choices amongst consumers.

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Ranking at the very top, this fish tank has a triple strong bottom with clear glass welded together with silicone rubber which makes it sturdy and durable. It comprises leak-proof technology and is suitable for both, freshwater as well as saltwater. Besides that, it consists of an aesthetic look that’s sure to look great in your room.

Key features:

  • Bottom and sides made up of triple-strength clear glass welded together with silicone rubber
  • Durable and leak-proof that will last you a long time
  • Great with saltwater and freshwater
  • Aesthetic looks

2. OCEANIC SYSTEMS INC. All Glass Aquarium AAG10021

OCEANIC SYSTEMS INC. All Glass Aquarium AAG10021
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Featuring another classy fish tank that comprises of high quality construction which is great for freshwater. It comprises of clean silicone edges which ensure a sleek look. Furthermore, the aquarium can be seamlessly placed on a stand and with the crystal clear glass, the view will be beautiful.

Key features:

  • Premium quality with excellent glass construction
  • Suitable for freshwater
  • Consists of silicone edges and can be placed on a stand easily
  • Sleek and modern look
  • Your aquatic plants and fishes will be visible too

3. Tetra ColorFusion Aquarium NV33822

Tetra ColorFusion Aquarium NV33822
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Available in: Australia, Canada, UK and US

Featuring yet another classy option in terms of 20-gallon fish tanks, this one is surely a keeper. It comes with LED lights, a hood, heater, as well as filter too. It comprises a color changing LED which can make your fish tank look beautiful. Besides that, it is made up of durable material that will last you a long time.

Key features:

  • Comes with color changing LED light which can make your fish tank look beautiful
  • Comes with a filter, heater and a lot more
  • All in one package that will make your life easier if you love having aquariums at your home or workplace
  • Irresistible looks and a lucrative package

4. GloFish NV33823

GloFish NV33823
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Available in: Australia, Canada, UK and US

Similar to the one mentioned above, this one too, will surely impress you just by the specifications of it. It is made up of high-quality materials and comprises of a blue LED light which will transform the look of your fish tank entirely. Furthermore, it comes with an all-in-one package that includes a heater, filter, plants and a lot more.

Key features:

  • Comes as an all-in-one package – heater, filter, hood, etc.
  • Comes with an attractive blue LED light to make your fish tank look beautiful
  • Made up of scratch resistant glass that is durable and long lasting
  • Cost effective

5. Lifegard Aquatics R460086

Lifegard Aquatics R460086
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Available in: Australia, Canada, UK and US

Presenting you an option you won’t be able to resist. This ultra simplistic, yet a modern fish tank is not just convenient, but also consists of excellent quality. It features a clear glass view with excellent craftsmanship. It even has an insulation pad for tank base protection. Besides that, it also has a black dense foam leveling mat for extra coverage too.

Key features:

  • Clear glass view – makes your tank appear pristine and beautiful
  • Excellent craftsmanship and has an insulation pad for tank base protection
  • Comes with a black dense foam leveling mat too
  • Good brand reputation – deemed as reliable by most customers

6. Marina Aquarium Kit 15266A1

Marina Aquarium Kit 15266A1
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Available in: Australia, Canada, UK and US

If you’re still not impressed with the tanks mentioned above, then this one is sure to make you awe-inspired. This tank can accommodate many props and would be ideal if you want to decorate your aquarium. It consists of a slim filter with quick filter change and includes everything you’d ever want in a fish tank. With the ideal dimensions, it won’t be difficult to buy a stand either!

Key features:

  • Marina slim clip-on filter with quick filter change – saves time and effort
  • Can accommodate many props and fish at a time
  • Ideal dimensions for which stands are readily available
  • Can be decorated with finesse

7. Aqueon Aquarium Fish Tank 100530578

Aqueon Aquarium Fish Tank 100530578
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Available in: Australia, Canada, UK and US

Here’s another option for all the aquarium enthusiasts. This one is sure to make you sold at the very first glance. It comes with a lucrative package and contains all you need for an attractive aquarium. It comes with a quiet flow power filter, along with an LED hood, premium fish food, and a lot more. It’s not just economical but will last you a long time as well, owing to the premium quality.

Key features:

  • The lucrative package that contains all the necessary requirements of a fish tank
  • Includes an LED hood, quiet flow power filter and a lot more
  • Durable and high-quality construction
  • Customize it however you like by adding your favorite plants and décor

8. Allcolor Ultra Clear Rimless Aquarium

Allcolor Ultra Clear Rimless Aquarium
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Available in: Australia, Canada, UK and US

Another great fish tank that you should consider would be this one. Since a fish tank is like a breathing ecosystem for the fishes, investing in a high-quality fish tank makes sense. Not only is it important for your home beauty, but it is equally important for the underwater species. This tank comes with high quality and appears crystal clear. It is strong and durable too.

Key features:

  • High quality and crystal clear
  • Easy to clean with a sleek appearance
  • Comes with a base mat and cleaning cloth
  • Will last you a long time

9. SeaClear X1010012200

SeaClear X1010012200
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Available in: Australia, Canada, UK and US

Featuring a simplistic, yet a classic design in terms of fish tanks, this one’s a keeper. It comes with acrylic material which is deemed as clearer than glass and stronger than it. It is lightweight and won’t crack or chip easily. It is safe for both, salt and fresh water and is safe for your children, as well as the fishes too.

Key features:

10. Nano Rimless NRL-20

Nano Rimless NRL-20
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Available in: Australia, Canada, UK and US

Last, but not least, this fish tank comes with a unique design and is different from the rest, as it is not rectangular. It’s an all-in-one aquarium with an integrated sump and filtration to make the process easy for you. It has a space-saving design and can be ingrained into a wall as well. Moreover, it has a sleek and modern appearance.

Key features:

  • Sleek and modern appearance
  • Unique shape
  • The compact and sturdy design which will last you a long time
  • Made up of excellent quality glass


All in all, it can be said that 20-gallon fish tanks are a must-have and can be great for beginners. Since larger tanks ensure pH levels remain balanced and there’s more consistency in them, than smaller tanks, it’s best for everyone to opt for these. You can save your costs by integrating the tanks into the walls or corner walls and even side tables to avoid buying expensive stands.

Modern aquarium designs and home interiors facilitate cost-effective strategies to make your fish tanks stand out from the rest. Not only can you get your personal getaway if you own an aquarium, but it will make your house and rooms appear ultra-modern. The same applies to offices and communities. Hence, it would be safe to say that 20-gallon fish tanks would be the right choice for most people. Good luck finding yours!

Scott Evans

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