How to Aquascape a Reef Tank — Rock Work Tips & Techniques on the UNS R90

Great rock work is the foundation of any reef tank — and it's a lot harder than it looks. In this video, Henry and Nick from Nature Aquariums set up a UNS R90 reef ready system in the store and walk you through the exact techniques they use on real customer installs. From egg crate to CA glue to two-part epoxy, this is how the pros build rock scapes that look great, stay put, and stand up to years of use.

Why You Should Always Use Egg Crate

Egg crate gets placed on the bottom of the tank before any rock goes in, and most people misunderstand why. It's not about weight distribution — the bottom glass of these tanks is engineered to handle full rock loads. The real reasons egg crate is essential:

• Prevents sliding — bare glass is slippery. Without egg crate, rocks shift as you try to build arches and stacked structures. Egg crate gives your rock something to grip.
• Repositioning without destruction — if your scape ends up too close to the back wall or needs to shift left or right, egg crate lets you slide the entire structure across the glass without knocking it apart.
• Critter safety — snails, gobies, and starfish will hit the egg crate and turn around instead of getting trapped underneath rockwork.

The one exception: bare bottom tanks. If you're going bare bottom, you'll need a different solution.

Find the Mechanical Fit First

Before any glue comes out, find where your rocks fit together naturally. Glue and epoxy are not structural on their own — they lock pieces in place, but the rock work needs to be mechanically sound first. If two pieces don't sit together well, no amount of adhesive is going to make that joint strong. Take the time to find the right fit, then bond it.

Two Little Fishies CoralBonder — CA Glue & Powder

Henry uses Two Little Fishies CoralBonder system: a very thin, liquid cyanoacrylate (CA) glue paired with a binding powder. Here's how it works:

1. Apply the powder first to the contact area
2. Apply the CA glue on top — it reacts with the powder instantly and creates an extremely hard bond
3. Work fast — this stuff sets on contact

The result is a rock-hard fused joint that's much stronger than CA glue alone. Perfect for locking flat pieces together and building up structure quickly.

Two-Part Epoxy — When to Use It

Epoxy is a different tool and works differently than CA glue. It's not a contact adhesive — it doesn't bond on touch. Instead, it works by bridging a gap between two surfaces. The technique:

1. Knead both colors of epoxy together thoroughly until fully blended — this activates the bond
2. Spread it across both surfaces you want to join so it creates a physical bridge between them
3. Once hardened, it grips both sides and holds them together

Use CA glue for quick contact bonds. Use epoxy when you need to bridge a gap or add extra reinforcement. Use both together on critical joints for maximum strength.

Scape Design Tips

• Leave swim-through space — make sure there's good flow and open area behind and around the rock work. Nothing should lean against the back glass.
• Add texture to flat cuts — most aquacultured rock comes in flat-cut pieces. Stack smaller pieces around them to create ledges, overhangs, and jagged edges. This gives the scape life and gives corals natural places to grow.
• Think long term — your scape will look bare for months before corals grow in and fill it out. Build it with the end goal in mind, not just how it looks on day one.
• Leave room to clean — your magnet scraper, your hands, and your fish all need room to move. Don't pack the scape so tight you can't maintain the tank.
• Mock it up first — lay everything out on a table or cart at the same scale as your tank before committing. Henry and Nick mock up on a cart next to the tank so they can reference what they have and what they need.

Video Chapters

• 0:00 — Introduction: scaping the UNS R90 reef ready system
• 1:00 — Egg crate: the real reason you need it and how to use it
• 2:30 — Mocking up the scape: layout and rock selection
• 4:00 — Finding the mechanical fit before bonding
• 5:00 — Two Little Fishies CoralBonder: CA glue and powder technique
• 7:30 — Two-part epoxy: how it works and when to use it
• 10:00 — Combining CA glue and epoxy for maximum bond strength
• 12:00 — Swim-through space and back wall clearance
• 13:00 — Adding sand and final scape review
• 14:00 — Design advice: flat cuts, ledges, and building for long-term coral growth

Bottom Line

A great reef scape starts with a solid foundation — egg crate, good mechanical fits, and the right adhesives used correctly. Take the time to mock it up, find your rock fits, and build something you're going to enjoy looking at for years. Your corals will fill in the rest.

We carry UNS reef systems, Two Little Fishies CoralBonder, reef epoxy, egg crate, and everything you need to build your scape at natureaquariums.com — shipped right to your door.