Aquarium Dimensions & Weight: Length, Width, & Height

Aquarium dimensions and sizes vary by brand and the type of aquarium. For instance, Aqueon might make its 20-gallon tank larger or smaller than Seapora‘s 20-gallon aquarium. It’s essential to know the dimensions of the tank as it lets you know which equipment is compatible with the aquarium. For example, when buying hoods, stands, covers, or lights for your aquarium.

By knowing the weight of your aquarium when it’s empty or full, you guess where you can put it and what type of stand can hold the weight. Things like decorations, plants, the thickness of the aquarium, and water quality all affect the weight. Saltwater weighs more than fresh water. So, the weights listed below are rough estimates to give you a bit of guidance.

Aquarium Dimensions Chart

Things To Consider About Aquarium Sizes

Small tanks, as per aquarium dimensions, range from 2.5 gallons to 15-gallon aquariums. These tanks are suitable for a single small fish or five small fish if you get the 15-gallon tank.

Small Tanks

Small aquariums need special care because they have a limited bio-load capacity. So, you need to set up proper filtration and not add too many fish or other animals to these tanks.

Medium Tanks

Mid-size fish tank sizes range from 20 to 40 gallons. Mid-sized aquariums are available in several shapes and sizes and they can house both freshwater and saltwater fish. Some of these aquariums include a kit with lights, filtration, and aquarium decorations.

Large Tanks

Large aquariums range from 50 gallons to 180 gallons. These tanks usually come in shapes like bow fronts and rectangles. Larger aquariums generally house coral and saltwater fish (marine animals).

Breeder Tanks

Breeder tanks usually have unique dimensions. For instance, instead of being rectangular, a breeder tank can be hexagonal. You don’t need to buy specialty tanks, but be aware of the different shapes and dimensions so that it fits where you plan to put it. For example, a 40-gallon breeder tank and a 40-gallon long tank have different sizes and weights (see chart above).

SMALL AQUARIUMS
Tank Size	L x W x H	Empty Weight	Filled Weight
2 1/2 gallon	12″ x 6″ x 8″	3 lbs	27 lbs
5 gallon	16″ x 8″ x 10″	7 lbs	62 lbs
10 gallon “Leader”	20″ x 10″ x 12″	11 lbs	111 lbs
15 gallon	24″ x 12″ x 12″	21 lbs	170 lbs
15 gallon High	20″ x 10″ x 18″	22 lbs	170 lbs
MID-SIZED AQUARIUMS
Tank Size	L x W x H	Empty Weight	Filled Weight
20 gallon High	24″ x 12″ x 16″	25 lbs	225 lbs
20 gallon Long	30″ x 12″ x 12″	25 lbs	225 lbs
25 gallon	24″ x 12″ x 20″	32 lbs	282 lbs
29 gallon	30″ x 12″ x 18″	40 lbs	330 lbs
30-gallon Breeder	36″ x 18″ x 12″	48 lbs	348 lbs
40-gallon Breeder	36″ x 18″ x 16″	58 lbs	458 lbs
40 gallon Long	48″ x 12″ x 16″	55 lbs	455 lbs
LARGE AQUARIUMS
Tank Size	L x W x H	Empty Weight	Filled Weight
50 gallon	36″ x 18″ x 19″	100 lbs	600 lbs
55 gallon	48″ x 13″ x 21″	78 lbs	625 lbs
65 gallon	36″ x 18″ x 24″	126 lbs	772 lbs
75 gallon	48″ x 18″ x 21″	140 lbs	850 lbs
90 gallon	48″ x 18″ x 24″	160 lbs	1050 lbs
125 gallon	72″ x 18″ x 21″	206 lbs	1206 lbs
150 gallon	72″ x 18″ x 28″	338 lbs	1838 lbs
180 Gallon	72″ x 24″ x 25″	430 lbs	1870 lbs
225 Gallon	72″ x 27.5″ x 27.5″	358 lbs	2158 lbs

Placement

You need to consider the space that you want to place your fish tank. Not only do you have to consider the dimensions and weight, but the whole setup. The setup includes lighting, filters, heaters, etc.

Other things to consider:

• Space the stand or cabinet.
• Space between the back of the aquarium and the wall.
• Free space around the front, sides, and above the tank.

You don’t want to keep your aquarium in high-traffic areas where you accidentally break it. You also don’t want too much traffic and noise that might startle fish and other animals. Don’t hang items over the aquarium. Don’t place the aquarium under shelves.

You need space behind and around the aquarium. So, choose a size that allows you to attach things like a power filter or canister filter. You may need an air hose, digital timer, heater, etc. So, access to a power supply is essential. You also have to have enough space so that you can maneuver around the tank for cleaning and maintenance.

Fish

The kinds of fish, shrimp, snails, freshwater clams, plants, crayfish, etc. all impact the aquarium size. Some species of fish or crustaceans are territorial and aggressive. Aquarium crayfish are one such species. So, in this case, a larger aquarium would be best to give all the animals enough space.

Some fish like Oscar Cichlids are big and need larger sized tanks to accommodate their size. Freshwater shrimp and freshwater snails can survive in smaller aquariums so long as you avoid overstocking.

References

• Standard Aquarium Size Charts – https://www.youtube.com/watch?v=K9w2wdVu130
• All Standard Aquarium Dimensions – Dynamic Chart – https://www.customaquariums.com/glass-aquariums/all-aquarium-standard-sizes.html
• What do you think is the most ideal aquarium size for the home? Why? – Reddit – https://www.reddit.com/r/Aquariums/comments/1ne405/what_do_you_think_is_the_most_ideal_aquarium_size/
• What size aquarium is best in terms of maintenance? – Reddit –https://www.reddit.com/r/Aquariums/comments/5xoca1/what_size_aquarium_is_best_in_terms_of_maintance/
• Best tank size for beginners? : Aquariums – Reddit – https://www.reddit.com/r/Aquariums/comments/2yr793/best_tank_size_for_beginners/
• Calculating Aquarium Volume – How Can I Figure Out How Much Water My Fish Tank Holds? – https://www.firsttankguide.net/calculator.php