Blubber Cove 2-Piece Corner Aquarium Tunnel – Easy Install for Hooded Tanks

The Blubber Cove 2-Piece Corner Tunnel is a slot-together corner cave designed for tanks where dropping in a single bulky cave is awkward — hooded aquariums, lidded nano tanks, tanks with cross-bracing, or built-in setups where you can't easily lower a 200mm cave through a small access opening. Ships as two smaller pieces that slot together at the tank corner under your substrate. Once assembled and buried, it functions as a single corner cave; the join disappears under the substrate. UK 3D-printed in aquarium-safe PETG.

Why a 2-piece design?

Many tanks aren't easy to drop decor into. Hooded tanks with tight access flaps, lidded nano cubes with small openings, planted tanks with cross-bracing, or built-in / wall-mounted aquariums all share the same problem: a single 200mm cave physically won't fit through the access. This cave solves that. Each piece is roughly 100mm — small enough to drop through almost any tank opening. You assemble the two halves at the corner under your substrate, bury, and the result is a single buried corner tunnel that buyers with standard open-top tanks would have bought as a one-piece.

Features

• 2-piece slot-together design — each piece fits through tight tank access openings
• Corner-fit shape — sits against the back 90° corner of the tank
• Slim 40mm profile — buries fully in shallow aquascape substrate
• Designed for hooded, lidded and access-limited tanks
• Smooth interior — safe for delicate shrimp moults and fry
• 3D-printed in Northumberland, UK from aquarium-safe PETG
• Ideal for shrimp colonies, corydoras and small community fish

Specifications

• Material: Aquarium-safe PETG plastic
• Standard size (2 pieces): Piece 1: 105 × 40 × 40 mm · Piece 2: 100 × 42 × 40 mm
• Standard assembled length: approximately 205mm
• Large size (2 pieces): Piece 1: 140 × 52 × 48 mm · Piece 2: 132 × 52 × 48 mm
• Large assembled length: approximately 272mm
• Placement: Back corner of tank, buried under substrate
• Substrate depth needed: 4-5cm to fully bury Standard, 5-6cm for Large
• Colours: Black, White, Beige, Marble Effect, Green
• Made in: Northumberland, United Kingdom
• Brand: Blubber Cove

Ideal for these tank types

• Hooded aquariums with limited top access (Fluval Flex, Marina, Aqueon kit tanks)
• Lidded nano cubes and bowfront tanks
• Cross-braced planted tanks where a single bulky piece won't drop through
• Built-in or wall-mounted aquariums with restricted access
• Tanks where you're rescaping without fully draining — assemble piece-by-piece
• Standard open-top tanks too — assembly is still quick and the result is identical

Suitable species

• Neocaridina and Caridina shrimp
• Corydoras (panda, bronze, pygmaeus)
• Kuhli loaches and weather loaches
• Small community fish — chili rasbora, ember tetra, CPD
• Shrimp fry and small fry of any peaceful species
• Bristlenose plecos (Large size)

How to install

1. Drop each piece individually through your tank's access opening
2. Position both pieces at the back corner of the tank, slot edges aligned
3. Push the pieces gently together — the slot join holds firm under substrate weight
4. Pour sand, gravel or aquasoil over the top to bury
5. Keep tunnel openings clear at each end so fish can enter and exit
6. Within hours, shrimp and bottom-dwellers explore and claim the cave

How is this different from your other corner caves?

The shipping format. This one ships in two pieces specifically to drop through tight tank openings — useful if you have a hooded tank, lidded nano, or any setup where a single 200mm cave is too bulky to manoeuvre into position. Functionally, once assembled and buried, it works the same as a single-piece corner cave. Pick this if your tank access is restricted; pick our single-piece corner caves (Underground Corner, Slim Against-Glass) if you have open-top access.

Frequently asked questions

Will the two pieces stay together once buried?

Yes — the slot join is designed to be load-bearing under substrate weight. Once buried, the substrate itself locks the pieces in place. The join becomes invisible under the substrate line.

Can I take it apart for cleaning?

Yes — gently lift each piece during deep cleans, rinse in tank water, reposition and re-slot. Most owners leave it permanently buried; debris washes through naturally during water changes.

Will it look like two separate pieces in my tank?

No — once buried under substrate, only the two tunnel openings (one at each end of the assembled cave) are visible. The join down the middle disappears completely under the substrate line.

What if I have an open-top tank?

It still works fine — assembly takes about 30 seconds. But if you have full open-top access, our single-piece corner caves are slightly more convenient since there's nothing to assemble. This cave is specifically for buyers whose tank access is restricted.

Is it safe for shrimp?

Yes. PETG is shrimp-safe (no copper, no leaching) and the smooth interior won't catch moults. The slot join is internal — shrimp can't get caught in it.

Does it work in saltwater tanks?

Designed for freshwater. PETG is inert but we don't currently certify saltwater longevity — for reef and marine setups, source dedicated marine-safe decor.

Can I assemble it outside the tank first?

Not recommended — the assembled cave is 205mm (Standard) or 272mm (Large), which defeats the purpose of the 2-piece design if you have restricted access. Assemble inside the tank at the corner.

Why buy from Blubber Cove

Original aquascaper-designed pieces, 3D-printed to order in our Northumberland workshop in aquarium-safe PETG. The 2-Piece Corner Tunnel was developed specifically for tanks where standard single-piece decor doesn't fit through the access — a real problem that's rarely addressed in aquarium decor design. Free UK delivery over £30.