Ever wondered what a negative space aquascape is? Many aquarists heard about it, but most of them don’t understand the concept fully. This article reveals what NSA is, what are the best features behind the idea, and more.
Negative space aquascape (NSA) refers to the space between the rocks within your aquarium. Aquarium owners encounter the problem that the aquarium looks too artificial. Stones scattered all over the aquarium often do not look neat. Reef keepers use negative space to make the aquarium more natural.
Supposing you don’t like questions to hinge on guesswork, you should read on to reveal all the details related to NSA. Once you understand the benefits and challenges of an NSA described, you’ll get traction in using this advanced reef-keeping technique.
What Is a Negative Space Aquascape (NSA)?
What is the definition of “negative space”? Simply, it is the area of your aquascape that does not include any rock. To put it another way, open sand space free of stones. These places serve a variety of purposes, both practical and decorative. For starters, negative space “breaks up” lengthy stretches of rockwork, giving aesthetic interest. Creating a focal point in an aquascape is much easier when an open region breaks up the visual “monotony.”
On a practical level, negative space helps fishes divide territories, as seen by a tank aquascaped with several rock “bommies.” Each “bommie” may serve as a home for fish and corals alike. If you are tempted to combine aggressive coral species, isolating them on their separate rock bommie provides them a fighting chance. I have always liked many minor aggregations of rock spread around the tank and will continue to do so.
Breaking up “territory” isn’t simply crucial for keeping aggressive specimens away; it may also serve as an “aesthetic boundary,” enabling you to experiment with different methods, colors, and coral morphologies on other structures.

More about NSA
You can also move a lot of water if you use negative space correctly. The “gyre flow” frequently mentioned in fish geek circles works exceptionally well in this aquascaping design. Negative space truly brings a deep (i.e., deep front-to-back) tank to life, and even a tiny aquarium may appear more prominent when every square centimeter is not stuffed with rocks. Creating channels and open places simplifies maintenance. Because you won’t have to struggle with massive rock walls, entry to many regions of your tank should be relatively straightforward.
Imagine being able to insert a siphon hose into the aquarium without disturbing the corals! You’d be able to operate in the tank without the worry of being destroyed! In fact, why not use the sand to grow corals?
It’s ultimately up to you, but if you want to try something a little different, leave some free space in your rockwork and see what it can do for your aquascape. I believe you and your fish will like the open space.
By properly exploiting negative space in your aquascape, you will also achieve “forced perspective,” which will make the aquarium appear much larger and/or deeper than it actually is. It’s a crucial method in this era of tiny “nano” aquariums that might mean the difference between dull and spectacular! So, for the first time in my life, I’m advising reefers to “embrace the negative!”
Why Do You Need a Negative Space Aquascape?
Many aquarium owners use negative space aquascape to make their aquarium look more beautiful and natural. However, negative space aquascape can also help you with a variety of problems in your aquarium.
For example, if you have aggressive plants or corals in your aquarium, you can design the rocks to create a protective layer of stone between the passive and aggressive corals. By fencing off passive corals from the long and dangerous tentacles of aggressive corals, you are protecting weaker corals from stronger ones.
You can also use different tools and materials to give your stones almost any shape. In this way, you can fill or create a void in your aquarium, creating beautiful shapes all along your tank.
What Are the Benefits of a Negative Space Aquascape?
I prefer splitting benefits into two major groups: Aesthetic and practical benefits. Let’s consider practical benefits with an example first.
Practical Benefits of an NSA
Here is the list of key benefits in terms of usage:
- Adjusted water flow around the rockwork
- You have more options to place corals creatively
- Fish have more space to swim
- Reduced aggression. Separate aggressive and passive species
With the NSA aquascape, you can have a luxurious and natural aquarium that reminds you of the seashore all year round. The main advantage of the NSA is the shape of the stones you can achieve. You can combine any shape, size, and type of stone to get what you want. Stones can differ in structure, color, and density. Thus, you can choose a variant that will make you happy every day.
But the appearance is not the only advantage of the NSA. Properly built stones can completely solve or significantly alleviate a variety of problems in the aquarium. For example, a well-built system of well-shaped rocks can change the aquarium’s speed and direction of water flow, changing the distribution of fish waste, substances, and minerals inside the aquarium.
Now let’s have a quick look at the practical usability of an NSA.
NSA Practical Usability Example
Let’s say your aquarium stands near a window and the left side of it gets sunlight. Because of this, several species of fish that swim in your aquarium accumulate in the shady part of the aquarium to avoid overheating. Thus, all the waste will first fall into the right side of the aquarium, and then the water flow will carry them all over the aquarium.
You can enhance the filtration system by adding some absorbents, such as carbon. In this case, you run the risk of shifting the equilibrium within the aquarium, which will cause a lot of unpleasant consequences to solve.
On the other hand, you can use the negative space aquascape to solve the problem. By changing the shapes, you can change the water flow as well. In this way, the fish waste will be spread around the aquarium more slowly, allowing you to remove it manually or wait until the filtration system cleans the water itself. In our theoretical example, you could place the filter near the right side of the aquarium for additional effect. The filter would then be close to the fish waste and remove it quickly, as the intelligently arranged NSA weakens the water flow.
Aesthetic Benefits of an NSA
An open rockwork structure leads the eye through, around, and beyond the aquascape, adding depth and dimension. You know you’re staring at an aquarium, yet your imagination detects something—perhaps the huge ocean—beyond the building you’ve built. The bigger the tank’s front-to-back size, the more dramatic this impact. In contrast, the typical rock wall creates a flat, two-dimensional image even when bristling with brilliant corals.
While typical reef-tank aquascaping is best observed from the front of the tank, systems that effectively use negative space provide visual appeal from almost any angle or vantage point since the livestock grows and swims in all directions. When the tank is placed away from a wall, such as when used as a room divider, you may see and enjoy the system from the front, rear, and perhaps one or both sides.
What are the challenges of a Negative Space Aquascape?
The biggest challenge when using NSA is the materials and methods of joining them. Many aquarists use cheap or unproven brands of glue and stones to save money. This is understandable since the most popular products cost a lot of money. For example, to build an NSA, you may need 3 to 7 products.
Some aquarists claim NSA doesn’t look like they can hold up much weight as they branch out. The structural integrity of the rocks is the biggest challenge you may face. If you doubt the quality, drilling holes and putting acrylic rods is an option to go for. Another popular forum idea to fix branches is to punch holes in smaller rock sizes to try and string them together. However, my biologist friend and I tested it out. Even short-term results are not promising. Would the rock-stringing method add that much support without bending themselves under the weight of horizontal loads? Shortly — no. You can save some time on not testing the theory.