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How Much Does A Fish Tank Weigh? [5, 10, 20 Gallons And More]

When you want to keep fish as pets, you'll need an appropriately-sized aquarium. There are many sizes you can pick. However, another aspect you'll have to consider is the weight. How heavy can they get? If that's your concern, let's discuss the details. 

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Looks can be deceiving. Even the smallest aquarium carries a bit of weight. From 2.5 to 15 gallons, a filled aquarium can weigh around 27-150 pounds. 20- to 40-gallon fish tanks can weigh as much as 225-455 pounds. 

Unsurprisingly, water isn't the only additional weight a fish tank carries. You also have to think about the decor. The substrate you use also adds weight. We'll discuss everything you need to know in detail. To learn more, keep reading. 

A huge aquarium with gorgoeus aquascaping and hanging lamps on top, How Much Does A Fish Tank Weigh? [5, 10, 20 Gallons And More]

Fish Tank Weight By Size

Before you get pet fish, some pet stores will warn you that they need an appropriate-sized tank. Maybe you already know the type of fish you want to own. Some fish may require up to 125 gallons of water to live comfortably. 

A gorgeous aqua scaping fish tank inside a living room

Before purchasing the fish tank, you'll need to ensure it will go in a spot that supports the weight. It will also need a stand that can hold it. Let's get into the basics of setting up an aquarium. 

Understanding The Basics

Before we get into the specifics, let's break it down. Since fish tank sizes go by the gallon, we'll need to know the weight of a gallon of water. One gallon of water weighs 8.33 pounds.

However, salt water is a bit denser. One gallon of salt water weighs 8.6 pounds. Though, most people like starting with freshwater aquariums. 

If we fill in a 2.5-gallon tank, it will weigh around 21 pounds. The tank itself weighs approximately 3 pounds. In total, the tank will weigh 24 pounds. 

However, it doesn't end there. You'll need a tank substrate if you plan on decorating it with aquatic plants. Most will be able to grow on any substrate. Your options include gravel, soil, sand, etc. 

The rule of thumb is 1 pound per gallon. That's if you only want a 1-inch bed layer. For a 2-inch layer of substrate, increase that ratio to 2 pounds per gallon. 

These are the typical additions to a fish tank. Now let's put this information into practice. We'll go over some examples using the smaller fish tanks.

The Weight Of Smaller Aquariums

A fishtank filled with fishes and other healthy plant life

As mentioned, a 2.5-gallon tank will weigh around 24 pounds. If we follow the pound per gallon rule, we'll add 2 pounds of substrate. That brings the total weight to 26 pounds. 

5-Gallon Fish Tank

Now let's take a look at a 5-gallon tank. The tank itself weighs approximately 7 pounds. When you fill it with water, it adds 42 pounds. To achieve a 1-inch layer of gravel at the bottom, we need 5 pounds of substrate. 

That brings our total to 54 pounds. As you can see, the weight is starting to increase. 

10-Gallon Fish Tank

At 10 gallons, we're reaching a point where most people won't be able to move the weight. The tank should weigh around 10-11 pounds. Once we add water and substrate, it reaches 103-105 pounds. 

15-Gallon Fish Tank

Multiply 15 by 8.33 to get the weight of the water. That gives us a weight of 125 pounds. The tank will weigh around 21-22 pounds. With the substrate, the total weight is 162 pounds. 

20-Gallon Fish Tank

At this point, you should have the gist of the situation. Multiply the size of the tank by 8.33. Thus, 20 gallons of water will weigh 167 pounds. The weight of the fish tank will vary at this size. 

Some fish tanks use glass panels, while others use acrylic. Glass is heavier than acrylic. In general, a 20-gallon tank will weigh about 25 pounds. Thus, the total weight of a 20-gallon is 212 pounds. 

A Recap Of How To Calculate How Much A Fish Tank Will Weigh

Since we've covered a lot of information with examples, we'll take a quick recap. The fish tank itself will vary in weight. In general, a glass tank weighs more than an acrylic one. 

20-180-gallon glass fish tanks will weigh around 25-338 pounds. Acrylic tanks will weigh about 50% less. If you want to know how much the tank will weigh once it's filled, multiply the volume (gallons) by 8.33. 

Then, you have to decide on a substrate. Of course, you can go with none at all. But, if you want to cover the bottom of the tank, you'll need to follow the pound-per-gallon rule. 

Aquatic plants will need substrate deeper than 1 inch. So, you might need to use a 2-pound per gallon rule. Fish tank covers, decorations, aquarium stands, and filtration systems add weight too.

Though, the weight of filtration systems for small tanks will be negligible. You'll need a sizable filtration system for fish tanks with 60 gallons or more. Therefore, you can expect to add up to hundreds of pounds more.

What Is The Best Location For A Fish Tank?

Live sea corals inside an aquarium filled with lots of fishes

Now we know how heavy a fish tank can be. But this raises the question: what's the best location for a fish tank? The first factor you want to consider is if your floors can support the weight.

Assuming you know that they can, you'll want to place the aquarium near a wall or in the corner. It might seem like a good idea to stand it near a window. The sun will be able to give the aquarium some natural lighting. 

The Downside Of Natural Lighting

However, there's a downside to that. Since you can't control the sun, the aquarium might receive too much lighting. As a result, the tank will suffer from too much algae growth. The sun also increases the temperature of the tank water. 

You'll want stability in the aquarium. Otherwise, the fish can quickly become stressed, leading to diseases and death. 

Electrical Sockets And Cleaning Accessibility 

The wall that the aquarium stands against needs an electrical socket. This way, you can easily power the filter, lighting, pumps, etc. However, it needs to be in a practical spot. 

More specifically, it should be near water sources. Otherwise, water changes are going to be a headache. It needs to be accessible on all sides. This way, you can maneuver around without too much trouble.

Noise Levels And Visibility

Some people want to own an aquarium to be the centerpiece of a room. Aquariums are crowd-pleasers. It draws all the attention if you decorate it nicely and get some unique fish.

For this reason, avoid placing the aquarium near other attention grabbers like TVs. Nevertheless, they need to be in a visible spot. This way, you'll have sight of it most of the time. 

It's a great way to observe water leaks, cracks, and fish illnesses. Fish also hate noise. If there's too much going on, they won't swim out of their hiding spots as often.

What Can You Use For Fish Tank Stand?

A living room aquarium with beautiful aquascaping

Water is heavy. You wouldn't want to place a fish tank on a wooden table that's already carrying a heavy load. Otherwise, it might collapse. 

So, you'll have a broken table, aquarium, and water damage to your floors. With so much at risk, you should get an appropriate aquarium stand. There are a few options to consider.

Repurpose Furniture

The first is to repurpose wood furniture for aquarium use. Still, make sure it can handle the load. It needs to be sturdy enough. In addition, it should be water resistant. 

There's no way to tell how much the furniture piece will be able to hold. As long as there's enough support underneath, it may be able to work. Nevertheless, be careful when going this route. 

It works better if you're planning on keeping a small fish tank. Here's a YouTube video discussing more on this topic:

Purchase An Aquarium Stand

The second option is to buy a dedicated aquarium stand. You have two material choices: wood and metal. Metal stands are typically lighter and stronger than wood. However, wood is the cheapest of the two.

Click here to see this metal stand on Amazon.

Click here to see this wooden stand on Amazon.

DIY Project

You could also make it a DIY project. If you plan to go this route, use cabinet-grade plywood. It's the standard for quality aquarium stand building.

What Fish Tank Should You Get For A Beginner?

If you're purchasing a fish tank to liven up a room, it's better to go with a mid-size fish tank (20-50 gallons). It's more eye catching for anyone that comes into the room. In addition, it'll require relatively less maintenance.

Smaller tanks might seem easier to keep. However, that's not the case. The water chemistry in small tanks can go south fast. In other words, it can become a death trap for your pet fish in no time.

Mid-size aquariums are more forgiving. It takes time for the chemistry of the water to change. In addition, it opens up the options of fish you have to choose from. After all, the fish inside is also important in building an aesthetically pleasing aquarium.

Final Takeaway

A huge aquarium with gorgoeus aquascaping and hanging lamps on top

Fish tanks are amazing to look at if taken care of properly. As we've found out, they can also weigh a ton! Do you plan on going with a small or big fish tank? We hope you found this informative. Good luck with choosing an aquarium!

Before you go, do you need help finding out how much other materials weigh? What about bricks? To learn more, check out:

How Much Does A Brick Weigh?

Are you planning on using a coffee table as an aquarium stand? For more information, check out:

How Much Weight Can A Coffee Table Hold?