Acrylic for fish tank, OK?The ideal material for Aquariums and fish tanks, acrylic is sturdy, durable, waterproof, and has the same crystal clear transparency as glass so that you can watch your fish as they go about their day. Even more importantly, sheets of acrylic can be bonded together through various methods, and once they have been, the area where the two sheets joined will be practically seamless, meaning no potential leaks.

Using acrylic to build aquariums and fish tanks is easy once you have the right tools and the know-how. You can cut sheets of acrylic to size yourself or if you’d prefer you can order cut to size acrylic sheets direct from Cut Plastic Sheeting; all you need to do is send us the dimensions you desire.

Acrylic for fish tank, OK?

Acrylic Aquariums & Plastic Fish Tanks

Depending on your level of ability, the tools you have and how daring you want to be you can make your fish tank as a simple box, complete with right angles, or you can round off the edges to make it more decorative. We will only be covering how to do the former, as the tools and expertise required to achieve the latter are quite advanced.

Step One – Dimensions

The first thing you need to do is decide how big you want your aquarium to be. You should consider the size of the fish you intend to fill it with, their number, and how large the room you want the tank installed in is. You may also want to look into the cost of a filtration system for larger tanks, if you’re thinking about going big.

Step Two – Cutting Acrylic

Assuming you have decided to cut your acrylic sheets to size yourself, you will need to clearly mark out where you are going to cut. Always leave the protective film that the sheets are delivered with on until the latest moment possible and do your markings directly onto it with a marker. If for what ever reason it is not on, use masking tape to show the cutting lines.

Step Three – Smooth the Edges

When you’re about to adhere two acrylic sheets together you must make sure that the conditions are perfect. Any two edges that will be bonded together will have to be flat and smooth, but most importantly they must be exactly the same size. Using a sanding block, sand the edges down starting with 120 grit paper and moving steadily up to 400 grit. Just to reiterate, you cannot marry two sheets together if either have rounded edges, so make sure they are flat.

Step Four – Using Acrylic Cement

There are several ways to bond two acrylic sheets together, but when using acrylic to build aquariums or fish tanks we’d recommend using a method known as ‘Capillary Cementing’. You will need to ensure that both sheets slot together exactly, or else you will run the risk of the bond not forming properly.

When joining two sheets side by side, use an applicator with a narrow nozzle to apply acrylic cement on both of the edges and hold them tightly together with clamp

When you’re bonding two sheets together to create a right angle, apply the cement along the inside length of the joint and clamp the sheets together firmly.

Give the acrylic cement a minimum of 48 hours to dry. When it becomes transparent you will know that it is dry.

Visit our blog page for more in-depth information on how to glue acrylic edges with acrylic cement.

Step Five – Piecing Acrylic Sheets Together

You should put your fish tank together carefully, and the more time you take to ensure that your acrylic sheets are prepared for joining the lower the chance that you’ll have to go back and rework your acrylic. Depending on how you have approached building your acrylic aquarium you may only need to attach the four side panels to the base. Either way, make sure that you bond every sheet that meet together with acrylic cement.

Step Six – Testing

Once dry, you should inspect your new fish tank and make sure that it is fit for purpose. Filling your aquarium with water and leaving it for a couple of days to a week is usually a good way of testing your handy work, and if by the end of that time no leaks have sprung you know things have gone to plan. If you do find a problem, depending on the severity, you may need to simply apply more cement or possibly replace the entire sheet.

Step Seven – Finishing Touches

Once you’re happy with your tank you can apply the finishing touches and give it a clean. Acrylic is very easy to maintain, and you will need little more than a moist cloth. Never clean the tank with an alcohol-based cleaner, as this will seriously compromise the strength of the material. You may also want to polish and smooth the top edges of the tank, which can be done in the same way as you smoothed the edges in step 3, but there are ways to apply a more comprehensive finishing.


Acrylic is often a popular option for manufacturers and hobbyists because it is both easy to fabricate and light weight. 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.


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 have big nasty blemishes 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.


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.


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 form 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.


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.


This is for a few reasons. 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 aquariums 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. Often times acrylic this thick is inevitably prone to impurities making it not so clear. The third reason is in 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 crap shoot 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 is 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.