Skip to Content

Acrylic Vs Glass Aquarium: Which Is Better?

The acrylic versus glass is an age-old debate in the fishkeeping hobby. If you are looking to buy a new fish tank and wondering which material is better, know this – there is no absolute answer. What’s the best fit for you may not be the best fit for someone else. The right way is to weigh the pros and cons of each (to see how one measures up to another) and decide for yourself.

The following is a detailed comparison guide to acrylic and glass aquariums. It sheds light on several factors you should take into account from the standpoint of building materials. We assure you that by the time you reach the end of this article, you’ll find it a no-brainer to choose between acrylic and glass.

A Brief Overview of Glass and Acrylic Aquariums

acrylic vs glass aquarium
A glass aquarium is simply glass panels joined together with the help of silicone. Standard glass and low-iron glass are two different types of glass used for making aquariums.

Fish tanks made of low iron glass are much clearer and don’t have the greenish tint regular glass has.

Acrylic is a transparent thermoplastic with outstanding strength, transparency, and optical clarity. Unlike glass, the acrylic sheets aren’t glued together but rather bonded into one piece to form aquariums.

Acrylic Aquarium Vs. Glass Aquarium – An In-depth Comparison

Both glass and acrylic come with their advantages and disadvantages, making them suitable for different preferences.

Acrylic Tanks Are Lightweight

Acrylic aquariums are approximately half the weight of glass aquariums that are of the same dimensions. Being lightweight, they are cheaper to ship and easier to move around.

The lighter the tank, the less weight on the stand. Keep in mind, with heavier aquariums you may be required to reinforce your flooring so it can withstand the load.

Acrylic Aquariums Scratch Easily

The main disadvantage of acrylic tanks is that they scratch ridiculously easily and there is no getting around it.

One has to be careful with cleaning and during the placement of rocks and substrate. Remember, all it takes is one tiny grain of sand or gravel trapped between the scraper and the panel to cause scratches.

Too many scratches accumulated over time lower the clarity of the tank and make it look old. But, the good news is – most scratches (be it inside or outside) can be buffed and polished using inexpensive scratch-fix tools or by paying a professional company.

When it comes to glass aquariums, standard glass has a much higher resistance to scratching. It won’t get affected unless mistreated with a sharp object and enough pressure.

On the other hand, low-iron glass can be easily scratched just like acrylic. If you don’t take precautions, you may end up scratching your tank, and those ugly marks will be noticeable due to the high clarity of the glass.

Glass Is Cheaper Than Acrylic

In almost all cases, glass aquariums are cheaper than acrylic aquariums with some exceptions to Starphire glass – the highest grade low-iron glass out there.

The price difference is quite significant; you may have to pay as much as 2 to 5 times more for an acrylic tank compared to a similar-size glass aquarium.

The price greatly varies depending on the volume and shape of the tank. Non-standard designs are often costlier.

Since glass aquariums are mostly mass-produced and are immensely popular, they tend to be cheaper unless you move beyond 125 gallons.

Acrylic Offers Better Clarity

When it comes to visual clarity, acrylic offers a high visible light transmittance of 93%, whereas Starphire allows 91% of light to pass through making it on par with acrylic clarity, and regular glass typically falls in the range of 82-89%.

The higher the VLT value, the greater the clarity.

Looking through acrylic and low-iron glass, you witness the true colors of the objects and inhabitants with utmost transparency and less distortion.

In standard glass aquariums, the colors inside don’t appear as clear and crisp. It also distorts the view by bending light. On top of it, the regular aquarium glass comes with a green tint due to the presence of an iron compound.

NOTE: Be it regular glass, Starphire glass, or acrylic, the clarity of the aquarium depends on the quality and grade of the material used by the manufacturer.

Acrylic Is More Durable Than Glass

Although prone to scratches, acrylic aquariums offer 7x higher impact resistance than glass.

Unlike glass, the acrylic sheets are welded into one piece which provides the tank necessary strength and durability to withstand impacts. A blow that would break a glass aquarium won’t have nearly as much effect on the acrylic one.

Moreover, with acrylic tanks, you are less likely to come across leaking issues or the seals coming apart.

Lastly, not to imply that glass aquariums are easily smashed. Unless you slam a rock onto the glass or hit it with something heavy, it’s unlikely your tank will break down.

Glass Tanks Are Easier To Maintain

Since there is less concern about scratching a glass aquarium, it’s easier to clean and to keep spotless.

On the other hand, cleaning an acrylic aquarium requires utmost care and most importantly acrylic-friendly scrapers and special liquid to avoid scratches. You can’t use standard magnetic and scrubbing pads on acrylic.

This will increase the overall maintenance cost but is always better than leaving ugly marks on the tank every time you scrape algae off the viewing panels.

NOTE: Even with the products that are specifically designed for cleaning acrylic aquariums, you have to take precautions. Because all it takes is one mishap to scratch all over your expensive aquarium.

Acrylic Offers Better Insulation

In comparison to glass, acrylic is a better insulator as it prevents heat loss in aquarium water and helps maintain a stable temperature for a prolonged time.

Acrylic tanks are an excellent choice when you are dealing with fish species that are sensitive to temperature fluctuations, or if power outages are a common occurrence in your area.

Talking about glass, it’s not only a bad conductor of heat but also a poor maintainer of heat. Glass aquariums gain/lose heat five times more quickly than acrylic tanks of the same thickness.

Glass Aquariums Are Readily Available

Due to significantly higher demand and being reasonably priced, glass aquariums have become commonplace and are easily available at any local fish stores, PetSmart and Petco.

On the other hand, acrylic aquariums (mainly the non-standard designs) may not be as easy to find in retail stores but they are readily available online and highly customizable for the size and shape you need.

Due to very little standardization from tank manufacturers, accessories such as hoods and stands may need to be ordered specifically to fit them correctly. This is especially true for the tanks with unusual shapes.

NOTE: If you are looking for good deals on used acrylic aquariums, check out Craiglist and Facebook Marketplace. But be aware and look out for scratches.

Acrylic Tanks Are Easily Modified

Owing to the flexibility of acrylic, it’s easier to mold and can be made into almost any imaginable shape or size.

The best part? Even when molded into curved designs like bowfront, quarter cylinder, etc, acrylic bends less light than glass, thus minimal distortion.

An ideal choice for DIY projects, acrylic is easily cut and drilled. Without the fear of breaking you can make way for pump outlets and overflows.

Glass, on the other hand, is too rigid and brittle which makes it difficult to shape. This is the reason why most glass aquariums are square or rectangular.

Moreover, when a glass is curved it tends to bend even more light, increasing the distortion. The inhabitants inside the aquarium may appear to be slightly bigger or smaller than they actually are, or their color may not seem quite true looking through the viewing pane.

Do Acrylic Aquariums Turn Yellow?

acrylic vs glass aquarium
Acrylic tanks turning yellow from UV exposure is a heavily propagated misconception on the internet.

The truth is: high-quality acrylic won’t turn yellow with age, but the alternative plastic blends will. The latter is merely designed to exhibit acrylic-like qualities but it’s not the real acrylic.

If you’re wondering how to distinguish between the fake and the real acrylic, you don’t have to. Simply ask your dealer or manufacturer for a warranty against tinting.

Nowadays, most acrylic aquariums come with a 10-year warranty that ensures no yellowing.

NOTE: It’s the UV inhibitors added during the manufacturing process that prevent the yellowing issue in acrylic aquariums.

Which Is The Better Choice For You – Glass or Acrylic?

As already mentioned in the introductory section, when it comes to choosing between an acrylic and glass aquarium, there is no one-size-fits-all recommendation.

Glass and acrylic both have a place in the hobby. After weighing the advantages and disadvantages of each, the decision comes down to individual preference.

The point is not which aquarium is better but which one suits you the most and aligns with your requirements. So use your discernment.

  • Acrylic aquariums are quite expensive. So, if budget is your primary concern, glass is the obvious choice you can save money on.
  • Similarly, when having a lightweight tank is your top priority (maybe you want less weight on your tabletop or flooring or simply want to avoid heavy lifting in the future), acrylic aquariums are the go-to choice.
  • Given how easily acrylic is scratched despite the significantly higher price tag, it might be a dealbreaker for some, especially when you have kids at home. Though scratches on acrylic can be buffed out and polished, think about how practical it is for you to do so.
  • While maintaining a glass aquarium is a breeze, keeping an acrylic tank clean and free from scratches requires extra care and attention to detail. So depending on how active and responsible person you are, either one would be an ideal choice for you.

Looking For an Aquarium Above 150 Gallons? Choose Acrylic Over Glass

acrylic vs glass aquarium
If you are wondering whether the above suggestion stands on a solid foundation of logical reasoning or is simply yet another opinion of the author. It is the former. And here is why:

  • When you buy a tank as big as 150 gallons (568 liters) or larger, an acrylic aquarium would cost you less than a glass aquarium. It’s due to acrylic being 50% lighter than glass, and thus cheaper to transport.
  • Since acrylic is welded together and made into one piece, it inherently possesses the strength to safely hold large water volumes while keeping the leaking issues at bay.
  • Acrylic tanks are also quite durable and shatter-resistant, so even if accidentally banged, the water is not going to be dumped all over your flooring.

How To Tell The Difference Between Glass and Acrylic Aquariums?

Following are a few ways to distinguish between glass and acrylic:

  • Acrylic aquariums don’t have silicone at the seams or corners as they are fused with acrylic cement. Only in glass aquariums, the panes are joined together with silicone.
  • Acrylic is a type of plastic, so when you tap on it with your knuckles or a coin, it sounds dull and hollow, similar to a plastic bucket. On the other hand, tapping glass produces a denser, higher sound.
  • Most acrylic tanks have a solid top with access holes cut out. Whereas glass is usually open with a center brace.

Conclusion

In a nutshell, acrylic is lightweight, offers better optical clarity, and is resistant to impacts but on the downside, it’s expensive and prone to scratches. Glass, on the other hand, is cheaper, easier to maintain, and doesn’t scratch easily but on the downside, it’s quite heavier.

Although we didn’t provide you with a cut-and-dry answer for which material is better, we hope the information shared above equipped you with enough confidence and clarity to decide on your own.