Why Are Fish Tanks So Expensive?

Why Are Fish Tanks So Expensive? (Detailed Explanation)

We are reader supported. When you purchase through links on our site, we may earn an affiliate commission. Also, as an Amazon affiliate, we earn from qualifying purchases.

If you’ve been hunting around for an aquarium because you want to take up the hobby or you’re a long-time aquarist, you may notice how expensive fish tanks are. They start out reasonable enough, $10 for a 10-gallon tank. But when you get into a 75-gallon tank or more, it can cost as much as $500. 

So why are fish tanks so expensive? Although it may seem irrational, high tank prices depend on the materials used, how big the tank is, how thick the walls are and the quality of the materials. Larger tanks have thicker walls and comprise better-quality materials than smaller ones. This is because the tank must be able to handle water pressure.

Why are fish tanks so expensive?

The various prices for fish tanks may appear to be irrational as the tanks increase in size. The reason for the expense has to do with construction, materials and other building costs that go into manufacturing.

Tank Materials

There are two different types of tanks: glass and plastic. The prices between each will vary greatly. Glass is never an inexpensive material and costs a pretty penny. Although plastic tanks can be less money than glass, it really depends on the size of the tank. This means certain plastic-type tanks will cost more than glass ones.


Glass producers not only require large amounts of sand melted down but also heat ranging in temperatures between 1,099°F and 1,501°F. They also must stay in a liquid state for long periods of time before formation. Therefore each piece of glass takes a huge amount of resources and energy along with the time and money it takes to maintain the material.

Why are glass fish tanks the most expensive to buy?

When it comes to aquariums, glass can be incredibly thick. Of course, there will be a difference in thickness when comparing a 10-gallon tank to a 75-gallon one. This is because the larger the tank is, the more water it has to hold. Ergo, the more stable and sturdy the tank has to be.

Since water is dense and heavy, it puts massive amounts of pressure on aquarium walls. So, the materials must be stable enough with strong adherence so that it won’t succumb to the force of pressure.

This is why you may find a 10-gallon tank for $10 and a 20-gallon for $40. It’s because manufacturers have to compensate for the size in relationship to the water it can hold. What’s more, the type of glass will also factor into the price of an aquarium.


Tempered glass is strong and toughened by quick melting and cooling. This means it can hold more water. It tends to be the most expensive kind of glass and where you will often see a jump in price according to the tank’s size.

The pitfall with this is if it cracks, it will shatter and this means no drilling prior to setting up your tank. It’s also vulnerable around the edges. But, it makes a great material for large tanks.


Also called flat or sheet glass, plate glass cannot hold as much water as tempered glass. But it works wonderfully for smaller aquariums. You can drill it, with subsequent cracking and not shatter it. This makes for a more affordable aquarium.

Why are some plastic fish tanks so expensive?

There are some tanks made of plastic that range in size and price. Sometimes they can be rather inexpensive but there are some that can be just as much as glass. For instance, an average five-gallon tank can comprise run-of-the-mill plastic. These aren’t very costly and are great for one fish or a small group of schooling fish.

In regards to larger tanks, like 150 gallons or more, they’ll often comprise a type of plastic called acrylic (see Amazon). This is stronger, lighter and more flexible than glass. What’s great about acrylic is that it can come in an array of shapes and sizes. This material can handle the water pressure inside the tank with ease. But, these can be even more expensive than glass.

Are freshwater aquariums less expensive than marine ones?

There is no variation in price for freshwater aquariums versus saltwater tanks. They are the same thing; it’s what you put in them that determines the difference. So, either type of setup will be appropriate for the same type of tank.

That said, saltwater aquariums are more expensive overall. But this isn’t dependent on the price of the tank. It’s more about the cost of fish, equipment, salination and etc.

Is it cheaper to get a custom-made aquarium?

No, it’s not cheaper to get a customized aquarium. Manufacturers build these on an individual basis to the specific preferences of the customer. But, they will build it exactly to size, shape and other types of bells and whistles that you won’t find in a store-bought tank.

Therefore, these can run between $750 to more than $7,000 to produce, whether acrylic or glass. You may be able to find a sale that certain companies run which can bring this price down. But they will not be less expensive than ones you can find at the store.

How do you find a cost-effective aquarium?

Because fish tanks tend to be expensive, it may be a good idea to employ a little savvy and resourcefulness. When you want an aquarium but don’t want to pay a lot of money for it, there are a few things you can try.

Used Aquariums

First, if you’re lucky enough to know someone who’s an aquarist, they may have an old tank lying around you can either have or buy. Also, there may be a rummage or garage sale in your area that could have one for sale.

Alternatively, you could page through the want ads or find an online forum that features the sale of aquariums around your location. You could have a used aquarium shipped, but the shipping costs may be as much as if you bought one from the local fish store.

Additionally, you could put a post on your social media page. Simply put out an announcement asking anyone if they have a tank for sale or know of anyone trying to get rid of one.

New Aquariums

In the case you’re not too keen on using someone else’s previously-used aquarium, you can shop around for new aquariums. It’s best to always start in your local area. Do some price comparisons between different pet and fish stores. Then, zero in on one and wait for a big sale.

Sometimes, your area or nearest largest city will have an aquarium convention or a fish keeping show. Although not guaranteed, you may be able to find a fish tank for a very reasonable price.

Build the Tank Yourself

If you’re the handy type and have the proper tools, you could build a glass aquarium yourself. This can be infinitely cheaper to afford, especially if you already have most of the materials and tools lying around. For this route, though, there are a few things to remember and take into consideration.

First, make sure you have the right tools. This will ensure your safety and reduce damage to the materials you use to construct the tank. But, many of the implements needed to build it are often commonplace in almost any household:

  • Strong duct tape
  • Paper Tissues
  • Scissors
  • Blade Scraper
  • Cleaning Wipes
  • Aquarium Silicone (it must be 100% hermetic for marine environments)
  • Silicone Dispenser
  • Sandpaper

Dimensions ; Configurations

Of course, you’ll also need glass or acrylic slabs. Remember, the walls of each opposing side have to measure the same. The front wall must be the same width and height as the back wall and the same goes for the side walls.

For the bottom, take note that the walls must sit/stand on the panel and not simply attach at the sides. So it should be either exactly equal to or a little larger than the total area around the tank. This will ensure the best seal with the silicone.

Then there’s the tank’s overall size. This will determine how thick the walls and bottom should be. The following are general ratios:

  • 0.2-inch thickness, up to 12 inches high
  • 0.4-inch thickness, from 12 to 24 inches high
  • 0.8-inch thickness, between 24 and 32 inches high

Final Thoughts

The reason why fish tanks are so expensive is mostly due to the materials. Glass will be expensive but acrylic will cost even more when you start getting into larger tank sizes, such as ones that hold 200 gallons of water. But, you don’t have to succumb to exorbitant prices if you find them to be outrageous.

You’ll just have to get a little creative and innovative in how you hunt down a fish tank. Stay on top of all local sales and search your area for used ones; ask friends and fish store clerks. For the more mechanically inclined, you can attempt to build it yourself.

See Also:
Is Cloudy Water Bad for Fish?
Can You Clean the Fish Tank Filter Cartridge?
How to Make Tap Water Safe for Saltwater Aquarium?
How to Raise Phosphate in a Reef Tank