How to Choose the Right Size Aquarium - Pet Hub USA

How to Choose the Right Size Aquarium

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Fish make great pets as long as they’re given plenty of room to do their thing! If you’re looking to get a few fish, make sure you choose the right size aquarium for them. Here are a few things to consider before buying an aquarium.

Below Ten Gallons

clear glass fish tank with blue fish
Photo by Vikram Mudaliar on Unsplash

If you’ve got one small fish, the smallest tank you should get is around 5 gallons. Anything smaller than that should be used only for aquatic plant life. That means the classic “fishbowl” style of tank isn’t a good habitat for a fish!

Eleven to Twenty Gallons

yellow fish in aquarium
Photo by Krys Amon on Unsplash

This might sound large to a newcomer to the hobby of keeping fish, but even a 20-gallon tank is somewhat small. You could potentially keep up to six fish under three inches in length in a tank of this size. Any more than that and you’d be looking to upgrade!

Twenty-One to Forty Gallons

Yellow and Black Fish in Fish Tank
Photo by Zana Di Carvalho on Pexels

Tanks in this range are well-suited to keeping between seven and twelve smaller fish. With this much room, they’ll have plenty of space to live and won’t encounter issues with wild swings in pH balance or buildup of waste materials. This also means you won’t need to clean them quite as often as smaller tanks.

Over Forty Gallons

aquarium, sharks, okinawa
Photo by JordyMeow on Pixabay

When you get an aquarium that holds over forty gallons of water, you’re getting into “centerpiece” territory. These can often be quite expensive and heavy. Make sure the floor of your home can stand up to the weight of a tank this size before you fill it up with water!


orange and white clown fish
Photo by David Clode on Unsplash

If you intend to keep saltwater fish, you’re going to need a saltwater tank. These are often larger and require more filtration than freshwater tanks. Keep in mind their higher maintenance and more demanding filtration needs before you adopt any saltwater fish.

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two Siamese fighting fishes
Photo by Worachat Sodsri on Unsplash

Keeping freshwater fish is notably a good bit easier than keeping saltwater fish. This is because their tanks are easier to clean, require less robust filtration, and can be somewhat smaller when you’re starting out. Popular freshwater fish like bettas and goldfish can be easier to care for than saltwater alternatives, too.

Glass Material

orange guppy fish
Photo by Nikhil Thomas on Unsplash

Glass aquariums are usually affordable but also fragile. They’re usually quite heavy and require a flat surface and an even weight distribution to keep any cracks from developing. The last thing you want is your aquarium springing a leak, harming your fish and ruining your floor.

Acrylic Material

blue and purple guppy fish swimming on aquarium
Photo by Tim Mossholder on Unsplash

Acrylic material is usually much lighter than glass and comes in a variety of designs. Usually, acrylic shows scratches more easily than glass but it’s also remarkably more durable against shattering. Consequently, acrylic also tends to be much more expensive than glass.

Read More: The 5 Best Types of Fish for First-Time Owners

Metal Base

RH Fish Tank
RH Fish Tank” by Daniel, Daniel Kwok is licensed under CC BY-NC-ND 2.0

Metal bases for aquariums tend to be extremely durable but also expensive. It’s a good idea to get a metal base if you’re getting a larger tank (such as an aquarium over 30 gallons). Just remember to check your floors and make sure they can withstand the weight of the base as well as the tank full of water.

Read More: 10 Things People Get Wrong About Pet Fish

Wood Base

125 gallon Fish Tank
125 gallon Fish Tank” by Scott Kinmartin is licensed under CC BY-NC-ND 2.0

Wooden bases tend to look more like furniture than metal bases, and they’re often more affordable. However, they can be less durable than metal and need to be painted and sealed to prevent water damage and warping due to exposure to moisture.

Read More: Saltwater Fish Tank Tips for Beginners

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