Aquarium Rocks for Natural Aquascapes, Inert Hakkai Stone in Blue-Grey Tones and 10–30 lb Sizes

Hakkai Stone brings the softly weathered character of river rock to planted aquariums, giving pet parents a natural focal point for calm, considered aquascapes.

Also known as Pa-Hai Stone or Bug Eaten Stone, it combines rounded forms, eroded grooves and muted blue, grey and green tones. Those distinctive details add depth without overwhelming delicate aquatic plants.

This dense stone is available in 10LB, 20LB and 30LB options. Ordering extra can provide more pieces and a broader variety of sizes for arranging a balanced hardscape.

Key Features

• Its inert nature means the stone will not alter aquarium parameters, making it easier to maintain the water conditions established for aquarium residents.
• Smooth, rounded shapes soften the overall layout, while naturally eroded grooves introduce the detail and character associated with long-term weathering.
• Blue and grey coloring, lifted by subtle green undertones, settles naturally into planted scenes instead of creating a harsh visual contrast.
• As one of the heaviest stones used in the hobby, Hakkai Stone gives each pound a substantial presence when planning the scale of a hardscape.
• Its appearance suits river-style aquascapes, structured Iwagumi layouts and calming nature aquariums, offering several clear directions for arranging the tank.
• Pairing the stone with delicate or grass-like aquatic plants creates a gentle transition between the hardscape and planted areas.

Specifications

• Also known as: Pa-Hai Stone or Bug Eaten Stone.
• Color: Blue, grey and subtle green undertones.
• Shape: Smooth and rounded.
• Surface: Naturally eroded grooves.
• Aquarium behavior: Inert and will not alter parameters.
• Weight options: 10LB, 20LB and 30LB.
• Density: One of the heaviest stones used in the aquarium hobby.
• Availability: Rarer and more limited than other popular stones used for planted aquariums.

Choose the weight that fits your layout plan, or order extra when you want more pieces and a wider range of sizes to shape a layered, natural-looking aquascape.