Hexagon Aquarium Sizes – The Ultimate Guide To Choosing And Stocking Them

Do you ever find yourself staring at a corner of your room, wishing you could fill it with a vibrant aquatic world, but a standard rectangular tank just won’t fit? I’ve been there, and that’s exactly why many of us turn to the stunning aesthetic of a six-sided display. Understanding hexagon aquarium sizes is the first step toward creating a thriving, vertical underwater garden that becomes the focal point of any room.

Don’t worry—while these tanks have a different footprint than traditional ones, they are a fantastic choice for both beginners and seasoned pros. In this guide, I’m going to walk you through everything you need to know about picking the right size, managing the unique dimensions, and ensuring your fish stay healthy and happy. We will explore how hexagon aquarium sizes impact your stocking choices and what equipment you’ll need to keep things running smoothly.

Understanding the Variety of Hexagon Aquarium Sizes

When you walk into a local fish store or browse online, you’ll quickly notice that hexagon aquarium sizes don’t follow the same “standard” rules as rectangular tanks. Because these tanks are designed to be taller rather than wider, their volume is distributed vertically.

Most manufacturers offer a specific range of sizes that cater to different spaces. Whether you are looking for a small desktop setup or a massive floor-to-ceiling showpiece, there is likely a hexagonal option that fits your vision.

Small Desktop Hexagons (5 to 15 Gallons)

Small hexagonal tanks are incredibly popular for offices or bedside tables. A 10-gallon hexagon is a common entry point. These are perfect for keeping a single Betta or a small colony of ornamental shrimp.

However, keep in mind that smaller volumes of water can be less stable than larger ones. If you are a beginner, starting with at least a 15-gallon setup gives you a bit more “buffer room” for water chemistry fluctuations.

Mid-Range Vertical Tanks (20 to 35 Gallons)

The 20-gallon hexagon tank is arguably the most popular size in the hobby. It offers a beautiful balance between a manageable footprint and enough volume to house a variety of small schooling fish.

If you have a bit more room, a 35-gallon hexagon tank is a fantastic upgrade. The extra height allows for more dramatic hardscaping, such as tall pieces of driftwood or stones that lead the eye upward.

Large Showpiece Hexagons (40 to 60+ Gallons)

For those who want a true “wow factor,” 50 and 60-gallon hexagons are the way to go. These tanks are heavy and require specialized stands.

When you get into these larger hexagon aquarium sizes, you can start looking at larger fish species that appreciate vertical swimming space. Just remember that the taller the tank, the thicker the glass needs to be to handle the hydrostatic pressure.

The Science of Shape: Surface Area vs. Volume

One of the most important things I tell fellow hobbyists is that a gallon is not always just a gallon. In a rectangular tank, you have a large surface area at the top where the water meets the air.

In hexagonal tanks, the surface area-to-volume ratio is much lower because the tank is narrow and tall. This is a critical factor for your fish’s health because most oxygen enters the water through the surface.

Managing the Gas Exchange Rate

Because of the smaller surface area, the gas exchange rate in a hexagon tank is slower than in a standard tank. This means you cannot stock a hexagon tank as heavily as a rectangular one of the same volume.

To compensate for this, I always recommend adding an air stone or ensuring your filter output creates plenty of surface agitation. This helps “break” the surface tension and allows more oxygen to enter the water while CO2 escapes.

Vertical Swimming Space

Fish like Neon Tetras or Danios love to zip back and forth horizontally. In a tall hexagon, they might feel a bit cramped because their “runway” is shorter.

However, for fish that move vertically or prefer to hover, these dimensions are a dream come true. Understanding how hexagon aquarium sizes affect swimming patterns will help you choose the right inhabitants.

Top Fish and Plant Choices for Hexagonal Tanks

Choosing the right residents is the most exciting part of the process! Since we are working with vertical height, we want to pick species that naturally utilize different levels of the water column.

Fish That Thrive in Tall Tanks

If you have a larger setup, such as a 35 or 60-gallon hexagon, Pterophyllum scalare (Angelfish) are the absolute stars of the show. Their tall, thin bodies are perfectly adapted for navigating vertical spaces and tall plants.

For smaller tanks, consider:

• Gouramis: They are labyrinth breathers and enjoy the ability to swim to the surface easily.
• Endlers Livebearers: These active little guys will explore every inch of the six sides.
• Hatchetfish: These stay at the very top, making great use of the upper water layer.

Selecting the Right Aquatic Plants

To make the most of the height, you need plants that grow tall and proud. Vallisneria americana (Jungle Val) is my go-to recommendation. It sends up long, ribbon-like leaves that can reach the surface of even the tallest tanks, creating a beautiful “curtain” effect.

You might also consider Amazon Swords or tall Ludwigia species. If you find the bottom of the tank is too dark for stems, try focusing on low-light plants like Anubias or Java Fern attached to tall driftwood.

Equipment Challenges and Solutions

Setting up a hexagon tank requires a few tweaks to your standard equipment list. Because the depth is greater than average, reaching the bottom for maintenance or ensuring flow reaches the substrate can be tricky.

Power Filter Intake Extensions

Most standard hang-on-back (HOB) filters come with short intake tubes. In a tall hexagon, the bottom of the tank can become a “dead zone” where waste collects because the filter isn’t pulling water from the lower levels.

I highly recommend using power filter intake extensions. By extending the tube closer to the substrate, you ensure that the entire water column is being circulated and filtered, preventing stagnant spots.

Lighting the Depths

Light loses intensity very quickly as it travels through water. In a deep 60-gallon hexagon, the light that reaches the bottom might be too weak for demanding carpet plants.

To solve this, look for high-intensity LED fixtures or “pendant” style lights that can be positioned directly over the center. If you aren’t using high-end lights, stick to low-light plants at the base and save the light-hungry species for the upper third of the tank.

Maintenance Tips for Tall Aquariums

I won’t sugarcoat it: cleaning a deep hexagon tank can be a bit of a workout for your arms! However, with the right tools, it’s a breeze.

1. Long-Handled Scrapers: Invest in a high-quality algae scraper with an extendable handle. You don’t want to be submerged up to your shoulder every time you see a spot of green on the glass.
2. Extra-Long Siphons: Standard gravel vacuums might not be long enough to reach the bottom while you remain standing comfortably. Look for XL versions.
3. Magnetic Cleaners: These are a lifesaver for daily touch-ups. Just make sure to get one rated for the thickness of your glass, as larger standard hexagonal dimensions often use thicker panes.

Unique Value: Hexagon Tank Setup & Stocking Checklist

To help you get started, I’ve put together this quick checklist to ensure your hexagon aquarium is set up for success from day one.

| Feature | Consideration | Recommendation | | :— | :— | :— | | Oxygenation | Low surface area | Add an air stone or sponge filter. | | Circulation | Tall water column | Use intake extensions on your power filter. | | Hardscaping | Vertical space | Use tall driftwood or “dragon stone” pillars. | | Substrate | Lighting levels | Use dark substrate to make plant colors “pop.” | | Planting | Depth | Place taller plants in the back/center. | | Stocking | Swimming room | Avoid “active runners” like Giant Danios. |

Safety and Structural Integrity

Before you fill your tank, we need to talk about weight. Because hexagon aquarium sizes often result in a “tower” shape, the weight is concentrated on a much smaller footprint compared to a long rectangular tank.

This creates significant hydrostatic pressure on the bottom seals. Always ensure your tank is sitting on a stand specifically designed for hexagonal shapes. A standard table might not be able to handle the concentrated load.

If you are setting up a 60-gallon hex, you are looking at over 500 pounds of water alone! Always double-check the floor’s structural integrity if you’re placing it in an older home. For help with the math, check out my guide on calculating tank weight.

Frequently Asked Questions (FAQ)

Are hexagon tanks harder to keep than rectangular ones?

They aren’t necessarily “harder,” but they require different considerations. The main challenges are light penetration and oxygen exchange. If you address those two things with good equipment, they are just as easy to maintain as any other tank.

Can I use a regular glass canopy?

No, you will need a specific hexagonal glass canopy. These are usually sold with the tank or can be ordered from the manufacturer. Because of the six-sided shape, a custom fit is required to prevent evaporation and keep your fish from jumping out.

How do I calculate the volume of a hexagon tank?

It’s a bit more complex than “length x width x height.” The formula involves the length of one side and the height. Most hobbyists find it easier to use an online volume calculator or check the manufacturer’s label.

Why does my hexagon tank look “blurry” from certain angles?

This is due to the refraction of light through the angled glass panels. Because there are more joints and angles than a rectangular tank, you may notice some distortion if you look through the corners. It’s just part of the unique aesthetic!

Is a hexagon tank good for a saltwater reef?

It can be done, but it is challenging. Reef tanks require high light and high flow. Getting enough light to corals at the bottom of a deep hexagon is expensive, and placing powerheads to avoid “dead spots” in a six-sided shape takes some trial and error.

Conclusion

Choosing between various hexagon aquarium sizes is a journey in balancing aesthetics with the biological needs of your fish. These tanks offer a unique, 360-degree viewing experience that standard tanks simply can’t match. By focusing on vertical-friendly species like Angelfish, ensuring proper gas exchange, and using the right maintenance tools, you can create a stunning aquatic pillar that thrives for years.

Remember, the key to success with a hexagon tank is not fighting its shape, but embracing it. Use that height to your advantage, grow those tall plants, and enjoy the unique perspective that only a six-sided world can provide. Happy fish keeping!