How Big is 20 Gallon Fish Tank?

A 20 gallon fish tank is approximately 24 inches long, 12.5 inches wide, and 16 inches tall.

This makes it a medium-sized aquarium that can hold around 15 to 20 small fish.

The water capacity of this size tank is roughly 19 gallons, though the manufacturer may state otherwise due to differences in measurements and shapes of tanks.

To ensure adequate swimming space for your fish, you should use no more than one inch of adult fish per 5 gallons (or 4 liters) of water.

A twenty gallon fish tank is a popular size for beginners and experienced aquarists alike.

It’s large enough to provide plenty of swimming space for most species, while still being compact enough to fit in small spaces or on tabletop surfaces.

This size tank can comfortably house up to four medium-sized fish and many plants, decorations, and other accessories.

With proper care, the twenty gallon aquarium can be a stunning centerpiece in any room!

20-Gallon Tank Dimensions in cm

The general dimensions of a 20-gallon tank in centimeters are 61 cm wide, 36 cm deep and 31 cm high.

Of course, these measurements may vary depending on the kind of tank you purchase, so it’s important to double check before making your purchase.

20 Gallon Long Tank Dimensions

A 20 gallon long tank is a perfect size for aquarists looking to start their own fish tank.

It measures 36 inches in length, 12 inches in width, and 16 inches in height.

This size of aquarium offers plenty of space for small fish and invertebrates, as well as decorations and plants.

Aqueon 20 Gallon Long

The Aqueon 20 Gallon Long aquarium is a great choice for hobbyists and fish keepers alike, offering plenty of room for larger fish species or an impressive display of smaller life.

With its durable construction and generous dimensions, the tank provides ample space to customize your underwater landscape with decorations, plants, and other aquatic features.

The included LED light fixture helps to create a beautiful atmosphere for your tank’s inhabitants while also providing essential illumination for plant growth.

Furthermore, the Aqueon QuietFlow Internal Power Filter will help to maintain water quality by removing debris and unwanted toxins from the tank.

20 Gallon Fish Tank for Sale

Are you looking for a 20 gallon fish tank to create the perfect underwater environment for your fish? Look no further!

We have a variety of 20 gallon tanks available, in different shapes and sizes.

Whether you’re just starting out or an experienced aquarist, our selection is sure to suit your needs.

Our tanks are built with quality materials and come equipped with all the necessary accessories such as filters, lights, pumps, heaters, decorations and more!

Shop today to find the right fit for your aquarium setup.

20 Gallon Tank Lid

A 20 gallon tank lid is an essential part of any aquarium setup. It provides a secure, airtight seal to keep your water and fish safe from outside contaminants.

It also helps regulate the temperature in the tank by preventing heat loss.

The lid should be made from durable material that is easy to clean and disinfect for optimal performance.

Many lids come with adjustable ventilation slots as well for better air circulation within the tank.

Investing in a quality 20 gallon tank lid will ensure you have a healthy, thriving aquarium environment!

20 Gallon Long Tank Lid

The 20 gallon long tank lid is the perfect accessory for any aquarium.

This sturdy and dependable lid provides an airtight seal to ensure that your fish remain safe, healthy, and secure in their habitat.

It’s easy to install with included hardware and will fit most standard-sized tanks.

With its durable construction and affordable price tag, this lid makes a great addition to any home aquarium setup!

30 Gallon Fish Tank Dimensions

A 30 gallon fish tank is an ideal size for many freshwater or saltwater aquariums.

It measures 36″ x 12″ x 18″, providing plenty of space for your aquatic creatures to explore and thrive.

This large tank also gives you the flexibility to create a unique underwater environment with plenty of room for decorations, plants, and other accessories.

With proper care, a 30 gallon tank can provide years of enjoyment as you watch your fish swim around in their home away from home.

20 Gallon Long Aquarium Kit

A 20 gallon long aquarium kit is the perfect way to get started with a freshwater or saltwater tank.

These kits come with all the necessary components for setting up and maintaining your own mini aquatic ecosystem, including a glass tank, light, filter system, heater, stand and substrate.

With this complete package you’ll be able to create an inviting environment for your fish and other aquatic creatures.

How Big is 20 Gallon Fish Tank


What Can I Fit in a 20 Gallon Fish Tank?

A 20 gallon fish tank is a great option for any aquarist looking to set up their first aquarium.

With the right setup, you can fit a lot of different types of fish in your 20 gallon tank.

Depending on the type and size of fish you’re interested in, you can easily house four or five small-sized species such as neon tetras or guppies along with two or three medium-sized ones like angelfish or discus.

If you want to keep larger species like cichlids, then one large variety should be enough to fill your tank – just make sure that there is plenty of space between them so they don’t fight.

It’s also important to consider how many plants and decorations you want in your tank before deciding which fish will go inside.

Certain kinds require more swimming room than others, so if possible choose ones that won’t overcrowd your aquarium too much.

A 20 gallon fish tank offers plenty of flexibility when it comes to stocking options.

With the right combination, it could become an interesting and vibrant home for many beautiful aquatic creatures!

How Many Gallons Does a 20 Gallon Tank Hold?

A 20 gallon tank is an incredibly useful size for a variety of applications, ranging from fish tanks to water storage.

A 20 gallon tank holds exactly 20 gallons of liquid; no more and no less.

Depending on the material used for your tank it may hold slightly less or slightly more than this amount due to expansion and contraction in temperatures.

It’s important to keep track of your exact measurements when using a 20 gallon tank since if you overfill it you could risk spilling or overflowing, which can cause major damage if not handled properly.

Depending on the application you’re using it for there might be restrictions as far as how much weight the tank can safely handle so always make sure that any liquids put inside are within these boundaries.

What are the Inches in a 20 Gallon Tank?

A 20 gallon tank is a popular choice for home aquariums, and it’s important to know how many inches of space you need if you’re considering one.

20 gallon tank will measure approximately 30 inches long by 12 inches wide by 18 inches tall.

This makes the total volume of the tank equal to 360 cubic inches; however, this does not account for any decorations or accessories that might be added later.

As such, when planning out your aquarium setup make sure you have at least 4-6 extra inches in length and width than what is advertised as the size of the tank so that there is enough room for everything inside.

How Heavy is a 20 Gallon Fish Tank Full?

A 20 gallon fish tank filled with water will weigh approximately 180lbs. This is because a gallon of water weights 8.34 pounds, so when multiplied by the 20 gallons of water, you get 166.8 lbs for the weight of just the water in the tank.

However, it’s important to note that this does not account for any décor or substrate which can add additional weight to your tank and should be taken into account when deciding if your stand or table can safely support it.

If you are using a gravel substrate at 1 pound per gallon, then an additional 20lbs would need to be added on top of the original 166.8lbs before setting up your aquarium, bringing us to our total weight estimate of 186 lbs for a full 20-gallon fish tank.


The 20 gallon fish tank is a great size for many types of fish and can be easily incorporated into any home or office.

It provides enough space to keep multiple species together in one environment, making it an ideal choice for both beginners and pros alike.

With the right maintenance and care, your 20-gallon aquarium will provide you with hours of enjoyment!