How to Concave Layout Tutorial (Intermediate Guide)

If you’re eager to take your aquascaping skills to the next level, mastering the concave layout is an excellent step forward. This intermediate guide will walk you through the design principles, material selection, step-by-step setup, and plant choices to help you create a striking concave aquascape. Ready to enhance the visual depth and natural appeal of your aquarium? Let’s dive in!

What is a Concave Aquascape Layout?

The concave layout is a popular aquascaping style characterized by higher hardscape and plants on the sides, sloping downwards to a central focal valley. This creates a captivating sense of depth, drawing your eye naturally towards the center. The concave style is perfect for intermediate hobbyists looking to experiment with perspective while maintaining a harmonious, natural feel.

Key Characteristics of the Concave Layout

• High sides, low center: Both hardscape and plants rise on the edges, forming a gentle valley in the middle.
• Central focal point: The lower center attracts visual attention, making it ideal for focal plants or open space.
• Illusion of depth: By sloping the substrate and arranging hardscape, you enhance the three-dimensional effect.

Materials & Tools You’ll Need

• Aquarium tank: 45cm to 90cm is ideal for beginners to intermediate aquascapers.
• Hardscape: Rocks and driftwood suitable for aquascaping (see our Best Aquarium Rocks guide).
• Substrate: Aquasoil or high-quality planted tank substrate.
• Plants: Ground cover, midground, and background plants (read on for recommendations).
• Aquascaping tools: Tweezers, scissors, and substrate spatula.
• CO2 system (recommended): For lush plant growth.
• Quality LED lighting: Suited for plant needs.

Step-by-Step Concave Layout Tutorial

1. Planning Your Layout

Sketch your layout or study inspiring concave aquascapes (check our aquascaping photo gallery). Decide where to place the highest points, focal areas, and open spaces. Composition is key – most classic concave layouts use the central third of the tank for the valley, with sloping heights towards the left and right sides.

2. Preparing the Substrate

• Use a sloped substrate bed – pile substrate higher on both ends (~3-6cm more than the center).
• Taper the substrate smoothly towards the center, forming a gentle U-shape.
• Use substrate supports, like mesh or rocks, to prevent slippage on higher slopes.

3. Placing the Hardscape

• Position larger rocks or driftwood on the ends of the aquarium – these will be your visual anchors.
• Arrange smaller stones or wood branches towards the center, keeping the lower profile.
• Angle rocks slightly toward the center valley for a natural flow.
• Check from different viewing angles and adjust for balance and stability.

For more hardscaping tips, visit our complete guide to aquascaping hardscape.

4. Plant Selection and Positioning

• Foreground (valley): Choose low-growing carpets such as Eleocharis parvula (Dwarf Hairgrass), Hemianthus callitrichoides (Cuba), or Micranthemum ‘Monte Carlo’.
• Midground: Plant medium height species like Staurogyne repens, Cryptocoryne wendtii, or Pogostemon helferi that transition up the slope.
• Background (sides): Use taller species — Rotala rotundifolia, Hygrophila polysperma, or stem plants that add fullness to the corners.
• Plant densely to ensure lush, healthy growth and prevent algae issues.

5. Filling and Cycling Your Aquarium

• Gently fill your aquarium to avoid disturbing your carefully built substrate and plants.
• Cycle your aquarium for at least 3-4 weeks, monitoring water parameters.
• Introduce fish and invertebrates gradually after ensuring the tank is stable.

If you’re new to cycling, learn more in our How to Cycle an Aquarium Guide.

Maintaining Your Concave Aquascape

Regular maintenance is crucial to keep your concave aquascape looking its best:

• Weekly water changes (30-50%) to prevent algae outbreaks.
• Trim and replant fast-growing species to maintain layout proportions.
• Monitor CO2 and fertilizers to support healthy plant growth.
• Clean glass and remove debris from hardscape for clarity.

For more tips, see our Aquascape Maintenance Guide.

Common Mistakes to Avoid

• Steep slopes: If the substrate gradient is too sharp, it may collapse over time. Create gentle slopes and use supports when needed.
• Unbalanced composition: Avoid crowding one side with too many large rocks or plants. Keep both sides visually balanced for a harmonious look.
• Overplanting or underplanting: Plant generously, but pay attention to plant heights and potential overgrowth.
• Neglecting light and CO2: Insufficient lighting or CO2 will cause plants to struggle, undermining your entire aquascape.

Concave Layout Inspiration

Many award-winning nature aquariums use the concave style for dramatic, immersive landscapes. Whether you prefer lush, jungle-like scenes or minimalist valleys, this layout offers endless creative opportunities.

For more inspiration, visit our Aquascaping Layouts Gallery featuring various concave designs from around the world.

Conclusion

Mastering the concave layout is a rewarding milestone in your aquascaping journey. With proper planning, thoughtful plant choice, and a commitment to regular maintenance, you’ll create a stunning aquascape that captures attention and brings depth to your aquarium.

Ready to try your own concave layout or looking to sharpen other aquascaping techniques? Explore our step-by-step aquascaping tutorials and join the Aquascaping Academy community for more tips, inspiration, and support!

Share Your Concave Aquascape!

We’d love to see your masterpiece! Share your photos or ask questions in the comments, or connect with us on social media. Your next aquascaping adventure starts now!