The Beginning

Hello everyone! I'm dedicating this blog series to sharing the knowledge and experience I've accumulated over many years of marine aquarium keeping. Each post will cover a specific topic in detail, so I strongly recommend reading through each topic from the start.

Let's dive in.

The first and fundamental topic is the display tank. Why start with the display? Because despite its apparent simplicity, it's an area where many beginners often make costly mistakes right from the beginning.

Glass Strength and Floor Safety

A common concern among newcomers is the fear that the aquarium might crack or that its weight could cause the floor beneath it to collapse. Let me reassure you: this is completely unfounded. If the floors in your home or apartment are structurally sound—meaning they're not rotten, creaky, or unstable—then you have nothing to worry about. Imagine this: I weigh about a hundred kilos, and when I jump, the impact at one point can easily reach 200–300 kilograms. If jumping in a small area of just 20x20 cm doesn't break the floor, then distributing two tons (2000 kg) over the larger area of an aquarium stand certainly won't cause any issues. You can safely put this worry aside.

Choosing the Right Glass Thickness

Determining the optimal glass thickness for your aquarium should ideally be guided by professionals experienced in aquarium building. However, if you’re a DIYer like me and want to build your own aquarium, you can check the calculator I’ve been using for many years. All the aquariums I’ve built so far, from 30 cm to 180 cm in size, have been based on this calculator.

Once the thickness is decided, minor surface irregularities underneath the aquarium aren’t problematic as long as you have a smooth and even cabinet with some soft padding in between. Aquariums have a certain degree of flexibility and can handle slight imperfections.

Many aquarium builders also recommend reinforcing the tank with longitudinal braces at the corners—transverse braces typically aren't necessary, given the lower pressure there. However, longitudinal braces are important to prevent issues like bubbling or peeling at high-pressure points, particularly along the front panel.

Using braces increases the thickness of the glue seams, significantly enhancing structural strength. Although it might not be the most visually appealing, it's undeniably practical. Again, consult your aquarium builder for precise recommendations.

Importance of Bracing (Reinforcement Strips)

People often question the necessity of installing braces or reinforcement strips. My advice: always use them. Early in my hobbyist journey, I made the mistake of prioritizing aesthetics over function, and I've deeply regretted it. Braces prevent fish from jumping out of the aquarium—a problem I've repeatedly experienced, losing numerous gobies that help stir the sand and manage detritus.

Even with just a few centimeters between the water surface and the tank’s edge, fish can still jump out easily, often ending up dried behind the cabinet within hours or a couple of days.

While a central brace might slightly obstruct the view or lighting, installing side braces (left-right and front-back edges) of at least three centimeters, preferably five centimeters for larger aquariums, significantly strengthens the tank. This reduces the required glass thickness, saving costs while maintaining safety. Many professionals will affirm that the benefits of braces vastly outweigh any minor aesthetic drawbacks.

Another advantage of braces is that they minimize water splashes when cleaning with a magnet scraper. Without braces, cleaning takes twice as long, as water continuously splashes out, requiring additional cleanup. Those who've experienced cleaning with and without braces understand this difference clearly.

Silicone Glue: Clear vs. Black

I've repeatedly emphasized this point: always use clear silicone glue. There's a widespread but false belief that black silicone is stronger or superior. In reality, clear silicone is visually cleaner, creating fewer visible boundaries and enhancing the aquarium’s overall appearance.

Clear silicone also has a critical practical advantage—it allows for quick detection of any damage or detachment between glass panels. With black silicone, spotting early signs of trouble is challenging and typically requires a flashlight and close inspection. Undetected issues can eventually cause catastrophic leaks, damaging your floors and equipment.

Moreover, once an aquarium is glued, you can’t immediately detect internal bubbles or defects due to the glue seam thickness of about 2 mm. Hidden defects might only reveal themselves after filling the aquarium, forcing you into costly and inconvenient reglueing. Using clear silicone mitigates these risks significantly.

Overflow Box: Internal vs. External

Overflow boxes come in two varieties: internal and external. Whenever possible, I recommend choosing an external overflow box. Internal boxes make maintenance and adjustments challenging because they require working awkwardly under the aquarium, often in cramped sump areas.

External overflow boxes are clearly visible and far more accessible, making adjustments and repairs straightforward. In case of leaks or other issues, you can simply lower the water level, remove the problematic overflow, and easily glue a replacement. Internal overflow leaks can gradually and silently drain your display tank into the sump—often unnoticed until significant damage is done, especially if electricity outages occur.

Furthermore, repairs of internal overflows are difficult, requiring draining water, cutting out the overflow, and re-gluing. External overflow boxes, by contrast, offer ease of access and straightforward replacement, ensuring your system remains operational with minimal downtime.

Repairing internal overflow boxes can quickly become expensive, time-consuming, and labor-intensive, which is why I always recommend going with external boxes whenever possible.

This overview should equip you with everything you need to effectively set up your aquarium’s display tank.

In the next installment, we’ll dive into sump systems.