Glass vs. Acrylic Aquariums

The Disadvantages of Glass Can be Engineered around — Acrylic’s Fatal Flaws Cannot

Acrylic is often a popular option for manufacturers and hobbyists because it is both easy to fabricate and lightweight. It takes a relatively extreme investment in tooling, equipment, and engineering to be able to cut and manipulate heavy sheets of glass. This is the main reason most custom aquarium manufacturers use acrylic, not because of the benefits of the material itself lends to the final product. Many hobbyists and small manufacturers can create custom aquariums with very simple inexpensive equipment. However, the end product is not so durable, and the material is very expensive. Below is a series of fatal flaws relating to acrylic aquariums that cannot be easily mitigated as they are inherent in the properties of the material.

Glass Aquariums Acrylic Aquariums
Ridged Panels
Free of Fabrication Flaws
Resists Absorption of Chemicals
UV Safe/Won’t turn yellow
No Visual Distortion
Curved Panels

When considering glass vs. acrylic aquariums, there are pros and cons to both. In the infancy of our service division, we spent a great deal of time evaluating what type of custom aquariums to use. We have not only immediate considerations of the installation difficulties to consider but the long-term viability of our investment. Once you analyze the difference the choice is quite clear. When it comes down to the decision of glass vs. acrylic aquariums, most often you are sacrificing a long-term benefit of glass aquariums in exchange for a short term benefit of acrylic aquariums. Our goal at Custom Aquariums is to mitigate the disadvantages of glass aquariums through our engineered fabrication, moving techniques, and ultra-clear material options with only advantages remaining.

Regular clarity vs ultra-clear glass

Acrylic Aquariums Scratch Easily

At the end of the day, acrylic is a type of plastic. Even if you take as many precautions as possible using so-called “acrylic friendly” scrapers and scrubbers, all it takes is one mishap of someone getting a grain of gravel or sand stuck in your algae scraper or cleaning pad and you will have scratches all over your expensive acrylic aquarium. Glass aquariums can scratch as well; however, it has a resistance to scratching many, many times greater than acrylic aquariums. Over the long haul, the acrylic aquariums will look old and beat up at a much greater rate than glass aquariums. Unlike a reptile cage where you can swap out the acrylic panels over time if they do get scratched up, there is no practical way to fix a severely scratched acrylic aquarium. As it is true that you can buff acrylic scratches, how practical is it to drain a fully established tank, introduce a series of chemicals/buffing compounds that can be dangerous to your fish? It is also extremely difficult to buff scratches out of acrylic and bring it back to its original clarity, particularly on the inside of a large, custom established tank.

Acrylic Aquariums Are Prone to Fabrication Flaws

Since acrylic is a flexible non-rigid material, the design/shape of the aquarium and quality and craftsmanship of the welding/fabrication is critical to the integrity of the tank. Much more so than the fabrication of a glass aquarium that has rigid panels. When welding the joints of an acrylic tank even the slightest oversight can lead to air bubbles in one of the joints compromising the integrity of the entire tank. Since glass panels are much more rigid, it is not necessary for the joints to be quite as perfect as in an acrylic tank in order for it to hold up over time. As a result, in our experience in the long run you will get far less probability of failure in a glass aquarium as opposed to an acrylic tank.

Acrylic Aquariums Become Yellow and Brittle Over Time

Another inherent flaw of acrylic is its inability to stand up to UV light, and yellow over time. There are many plastic materials out there that claim to be “UV Resistant”. That is exactly what it is, resistant, not UV proof. No acrylic is UV proof. Over the long run, there is no additive that can make plastic/acrylic stand up to UV light as long as glass. Eventually, the elements will get to it. Think of an old faded billboard… likely that billboard was printed on UV resistant vinyl. It may have held off for 5 years instead of 6 months, but eventually, it will fade and become brittle. When an acrylic aquarium starts to break down because of UV light either from the sun or from aquarium lights, it will turn yellow, become brittle, and can even crack and fail because of it. The more UV lights you have on your tank, or the closer it is to a window, the more accelerated this process will be.

Acrylic Aquariums Have Porous Material

At first thought many people don’t consider acrylic to be a porous material because after all, containers that hold water are made of it, right? This is true, but although water does not visibly pass directly through acrylic, it is absorbed by it and slowly leaches out the other side. What that also means is the various chemicals, bacteria, etc. that may be found in an acrylic aquarium, or the outside air for that matter, can work to deteriorate the acrylic as well as fester at the microscopic level. Think about an old dirty plastic container that has sat outside for years. There is nothing you could ever do to restore that item to its original condition. The UV light has taken its toll, and the chemical elements are impregnated in the material and has changed its composition forever. On the other hand, a pane of glass can endure the elements for generations. A good cleaning and it comes back to nearly its original condition.

Acrylic Aquariums Have Greater Visible Distortion than Glass Aquariums

This is for a few reasons. The first would be from the general clarity and quality of the acrylic used. Clarity can vary significantly depending on the grade and brand used by the manufacturer, and they might not always be forthcoming because high clarity acrylic aquariums are very expensive. It is important to know what particular clarity you are getting from any acrylic aquarium manufacturers and to be sure they are using what they say they are using. Second, because acrylic aquariums are so flexible the acrylic can bow significantly in the middle of the panel, even a thick panel with quality welds, much more so than glass aquariums. This bowing creates visible distortions. Larger custom aquariums in particular have to be made of exceedingly thick and expensive acrylic to prevent the acrylic from bowing, sometimes an inch or thicker. Oftentimes acrylic this thick is inevitably prone to impurities making it not so clear. The third reason is the general quality of the fabrication. Because the strength of an acrylic aquarium heavily relies on the weld rather than the rigidity of the panel itself, a great deal of the strength and potential distortion of the aquarium depends on the quality of the weld. It is a crapshoot if you happen to get a perfectly welded acrylic tank or not where you will see these distortions. Human error is an enormous factor, much more so than glass. Glass aquariums on the other hand are very rigid and comes from the factory perfectly flat with extremely tight manufacturing tolerances. Most of the distortion has more to do with the refractive light coming off the water in the tank (which you will get regardless of which type of material your tank is made of). And of course, if ultra-clear is what you are looking for we do offer ultra-clear glass for any panel that is amazingly clear for an extra charge. This has more to do with the clarity than distortion. Ultra-clear glass aquariums are made with less iron and therefore are slightly more transparent and clear than standard glass aquariums.