Acrylic or Glass Aquarium? | 2022 Buyer’s Guide

Nov 2, 2020

Acrylic Or Glass Aquarium

When it comes to hobby fish keeping, there are two schools of thought. The first one favors glass tanks, and the latter swears by acrylic ones. The debate on which is better, acrylic or glass aquarium, is never-ending. I have owned both kinds. 

And honestly, I think each of them has distinct personalities, not to forget, a few flaws. So, where do you fall? 

A Little History

Before we get into the ultimate smackdown, let’s go down a short trip down memory lane. 

Did you know the fishkeeping hobby dates back to at least the 14th century?

But the first modern aquarium, made with glass, was introduced and popularized by English naturalist Philip Henry Gosse in the mid-19th century.

And acrylic tanks weren’t even a thing until the late 1960s! Japan’s Mitsubishi Chemical Holdings introduced the world’s first acrylic resin panels for aquariums in 1966—and the rest is history.  

Now without further ado, let’s see how they fare against each other.

Acrylic Or Glass Aquarium?

Get Acrylic Aquarium Now.

Or, Go For A Glass Aquarium.

When gauging, which is better, I have taken the following parameters into considerations because I think these are the ones that matter the most to aquarists: cost, weight, support, scratching, room for customization, light refraction, and so on.

Keep reading to know!

Cost 

Winner: Glass 

This may sound a bit unusual, but glass aquariums are quite pocket-friendly than acrylic ones. 

Now that’s unusual because acrylic is considerably cheaper to manufacture and transport than glass. 

However, the reigning popularity of glass tanks and a higher number of suppliers manufacturing them helps keep the price relatively low. 

However, note that acrylic tanks have a cost advantage over glass after a certain point in size. 

For example, let’s assume you are shopping for a 150-200 gallons capacity. In that case, the glass tank will cost you more due to its weight and difficulty to transport. 

Weight

Winner: Acrylic 

In terms of weight, the unanimous winner ‘acrylic or glass tank’ showdown is acrylic!

Acrylic tanks are soft and very lightweight, unlike mineral-dense glass. Thus, they’re easy to be moved around and transport. 

For example, let’s take a 40-gallon fish tank with the following dimension: 36″ x 18″ x 16″

If the tank is made up of glass, it will weigh around 403lbs when filled with freshwater. 

On the other hand, an acrylic tank of similar dimensions will clock in at around 378lbs when filled to the brim with fresh water.

Especially when choosing a big aquarium, the weight your floor space can support is an essential factor. 

So, if you’re not sure about the final placement of the aquarium or the weight your floor supports, you can go with an acrylic aquarium. 

Scratching 

Winner: Glass 

Glass is the clear winner by miles when it comes to being scratch-proof. 

Because, at the end of the day, acrylic is plastic, and it will scratch. All it takes is one small gravel stuck in the algae scraper. Thus, you can only use acrylic-friendly scrapers or tools to clean the tank’s inside. 

Many acrylic polishing kits promise to clear the blemishes and deliver on them. 

However, when you have to clean the scratches inside the tank, you’ll have to drain it completely. Now imagine what a hassle that would be. 

It’s not that glass aquariums are entirely scratch-proof. But they are resistant to scratches by manifolds compared to acrylic. 

Thus, a scratched acrylic tank will look beaten up and old much faster. 

Room For Customization

Winner: Acrylic

If you have a knack for adding personal touches to the fish tank, an acrylic tank may be the answer for you. Since it is an entirely human-made synthetic substance, it can be given any shape you want—unlike glass mineral. 

You can also quickly drill holes anywhere you like for overflows, pump outlets, and so on. As a result, an acrylic tank allows greater flexibility for DIYs and customization. 

On the other hand, it will take a high degree of investment in time, tools, and equipment to manipulate thick glass sheets slightly. 

Thus, if you’re looking for tanks in versatile shapes or even get one custom made, an acrylic tank is what you need. It can be given your desired dimensions at a fraction of the cost. 

And that’s why it is trendy among avid hobbyists. 

Refraction Of Light

Winner: Acrylic

Acrylic has almost the same index of refraction as water. The image inside isn’t distorted in the aquarium because the light is bent just once or twice. 

So, you’ll only see a slight distortion in the placement of fish, but the color and size will remain true. 

On the other hand, glass and water have different refractive indexes. The light passes through air, glass, water, and fish before reflecting through the same route. 

Hence, each time the light is bent, the image is distorted slightly. And it’s even worse in thicker glass panels. 

However, most aquariums we have at homes and offices aren’t big or thick enough to distort the image significantly. 

Support

Winner: Glass

Due to high density, glass tanks can support comparatively more than their weight. That’s why glass tanks can be positioned on stands with an open or incomplete top. 

The high rigidity means that it requires less support at the top to keep the tank from splitting its seams under water’s weight. 

On the other hand, acrylic aquariums need more generous support across the top to keep the acrylic panels from bowing apart. 

If the stand doesn’t extend support across the base, the tank’s bottom can pull away from the seams under the water’s weight. 

However, these mishaps seldom occur. 

Insulation

Winner: Acrylic

When answering which is better, acrylic or glass aquarium, we often overlook one crucial aspect: Insulation. 

It’s common knowledge that fish need a stable temperature inside their tank—similar to how it would be in their natural habitat. Sudden change in the temperature—from cold to warm and vice versa—will only stress your tank’s little creatures. 

So, acrylic is better at it because it doesn’t have free electrons moving around when it comes to insulation. This property would be ideal for coral and reef setups! Glass—not so much!

Clarity

Winner: Glass

When new, acrylic and glass tanks provide almost similar levels of transparency and clarity. 

However, the potency of standing up against UV light is different. Prolonged exposures to light can make your acrylic tank brittle and yellow over time. If your tank’s exposed to direct sunlight or have UV lights, the process is even more rapid.

On the other hand, the glass will remain clear for many years, irrespective of how much light passes. That being said, intense lights are never a good thing for your tank. 

Many acrylic tanks are made to be UV resistant these days, but there’s a catch—they’re UV-resistant, not UV-proof. 

So, the victorious of acrylic vs. glass aquarium: clarity edition is glass!

Impact Resistance 

Winner: Acrylic 

In terms of accidents and mishaps, acrylic tanks can be more forgiving than their glass counterparts, prone to chipping and breaking. 

That’s because acrylic is sturdier than glass and at least ten times more resistant to impact. So, suppose you’re not too sure about the tank’s placement and need to have it moved around. In that case, acrylic is a relatively safer option. 

Seamless Corners 

Winner: Acrylic 

Acrylic tanks often come in rimless fashion—providing you an uninterrupted view of the tank and hence, the aesthetic appeal. 

The seamless view is possible because acrylic panels are glued together, invisibly in the corners. 

A glass aquarium is always held together by silicon sealant, which comes in either black or translucent options. 

You can opt for a translucent option to replicate that rimless look. However, since silicon tends to absorb fish treatment (which often comes in blue or green colors), the corners and seams will have a colored appearance after some time. 

So, that is a 10-pointer smackdown on the topic ‘which is better—acrylic or glass aquarium?’  

There are some tips to find out for those who already have one but aren’t entirely if it’s a glass or acrylic tank. 

How To Tell If A Fish Tank Is Glass Or Acrylic?

These things happen. When I first started, for a good time, I didn’t know the difference between glass and acrylic tanks. To me, they all looked the same and still do!

Here are a few tips:

  • Glass is relatively colder to touch than acrylic. If you press a finger against each tank, the glass will remain cool for a bit longer, while the heat from your hand will transfer to the acrylic tank faster. 

  • For this tip, gently knock on the tank’s surface. If it makes a short high sound like clink, it is probably glass. If the sound is dull and hollow, there’s a good chance it’s an acrylic tank. 

  • Most acrylic tanks come with a solid top and access holes drilled out, while glass tanks have an open top with a center brace. 

  • Acrylic tanks have a rimless look as they are fused with solvents. However, the use of sealant will make the seams of the tank look a bit greenish. 

  • A fun, bonus tip: Wet your finger and run it against the tank’s outer wall with a bit of pressure. If it makes a sound, like when someone is playing a saw, it’s mostly glass. 

What Would I Get? And What Should You Buy?

First things first. When deciding which is better, acrylic or glass aquarium, a good chunk of a tank’s longevity and performance depend on the quality maintained during initial construction. So, always make sure to buy from a high-quality manufacturer. 

As for what I would get, I’d probably buy a glass aquarium this time around. That’s because I have young children in my home, and they’ll scratch an acrylic aquarium in no time! To be honest, that’s the only turnoff factor about an acrylic tank for me. 

However, for my office, I have a rimless, hexagon-shaped tank that never fails to amaze anyone walking in—not to forget all the conversations it stirs. 

So, if you have garnered a fair bit of experience and are ready for the next step filled with potentials for customizations, DIYs, and heaps of aesthetic appeal, an acrylic tank is what you need. 

rohit gurung author at urbanfishkeeping

About Rohit Gurung

My never-ending love and fascination with Aquascaping started when I received a red-eared turtle for my 10th birthday.

Apart from researching and writing, I spend hours gazing at my 3 turtles. And yeah, I bask alongside them too.