Blubber Cove Circular Corner Aquarium Cave – Two-Entrance Tunnel Hide for Shy Fish

The Blubber Cove Circular Corner Aquarium Cave is a rounded, two-entrance corner hide built around a flow-through tunnel design. Unlike single-entrance caves where shy fish can be cornered by tankmates, this cave lets fish enter one side and exit the other — calmer behaviour, less stress, and a much higher chance your skittish species will actually use it. The circular silhouette also blends naturally into planted and hardscape aquascapes. UK 3D-printed in aquarium-safe PETG.

Why two entrances matter

Single-entrance caves are great for territorial cave-spawners — but for community fish, they're a trap. Corydoras, kuhli loaches, shy tetras and nervous shrimp avoid caves they can't escape through quickly. This is why fish-keepers often see their cave-decor go unused. Two entrances solve the problem: fish enter knowing they can leave the other side, so they actually claim the space as a daytime retreat instead of avoiding it.

The circular shape

The rounded form does two things. Visually, it reads as a natural stone outcrop rather than a moulded ornament — it slots into planted, hardscape and Iwagumi aquascapes without breaking the aesthetic. Behaviourally, the curved interior means fish never hit a flat wall, which matters for nervous species that startle and dart. Substrate can be layered on top to disguise it further.

Features

• Two entrances — flow-through design, fish never get cornered
• Circular silhouette — natural stone-look aesthetic
• Corner-fit shape — sits flush against the 90° back corner
• Substrate-friendly top — can be partially or fully buried
• Smooth rounded interior — safe for delicate fins and shrimp moults
• 3D-printed in Northumberland, UK from aquarium-safe PETG
• Ideal for shy nano fish and community setups

Specifications

• Material: Aquarium-safe PETG plastic
• Dimensions: 135 × 135 × 60 mm
• Entrances: Two — flow-through tunnel design
• Placement: 90-degree back corner of tank
• Colours: Black, White, Marble Effect, Moss Green, Sand
• Made in: Northumberland, United Kingdom
• Brand: Blubber Cove

Ideal for these species

• Corydoras (panda, pygmaeus, bronze, sterbai) — shoaling species that need group cover
• Kuhli loaches and weather loaches — wriggle-through cave behaviour
• Neocaridina and Caridina shrimp — colony grazing
• Shy nano fish — chili rasbora, ember tetra, celestial pearl danio
• Bristlenose plecos and small catfish
• Otocinclus and hillstream loach

Aquascape placement

Designed for the back-corner 90° of rectangular tanks 30 litres and up. Pair with low-light plants like java fern, anubias or moss to soften the silhouette. The circular form works particularly well in Iwagumi and Dutch-style aquascapes where stone arrangements dominate.

Also suitable for reptile setups

While designed for aquariums, the same flow-through circular shape works as a vivarium hide for crested geckos, leopard geckos and small reptiles or amphibians. Bury under coco fibre or reptile substrate for an underground burrow look. PETG is non-toxic in humid and dry environments.

Frequently asked questions

How is this different from your other corner caves?

Two entrances. Our other corner caves (Tall Mangrove, Wide Corner, Underground, Arch) all have one main opening. This one is a flow-through tunnel — fish enter one side, exit the other. That makes it the right pick for shy or shoaling species that won't use single-entrance caves.

Will my corydoras actually use it?

Yes — corydoras are one of the species this design was specifically chosen for. The flow-through tunnel matches their natural behaviour of swimming through under-rock spaces. Most owners report corys claiming the cave within 24-48 hours.

Is it safe for shrimp?

Yes. PETG is shrimp-safe (no copper, no leaching) and the smooth interior won't catch moults. The two openings give shrimp safe escape routes from larger tankmates.

Can I bury it under substrate?

Yes — the flat-ish top allows substrate to sit on top, hiding the structure further. Keep both entrances clear of substrate so fish can flow through.

Will it work in a community tank?

Yes — this is one of the best community-tank cave designs because no fish gets trapped. Aggressive tankmates can't corner peaceful species inside.

Is it suitable for reptiles?

Yes, as a secondary use. Crested geckos, leopard geckos and small snakes use it as a humid burrow when buried under reptile substrate. The two entrances are a behavioural plus for reptiles too.

Why buy from Blubber Cove

Original aquascaper-designed pieces, 3D-printed to order in our Northumberland workshop in aquarium-safe PETG. No painted resin, no imports, no surprises. Free UK delivery over £30.