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Black Lava Stone

Porous, textured black volcanic stone for aquascaping that hosts beneficial bacteria.

Natural stone: photos show typical pieces.

Regular price $18.99
Tax included Shipping calculated at checkout.
Size

Usually arrives in 2–5 business days

Delivery details

  • Dispatched within 1 business day
  • Proudly Kiwi since 2017
  • Expert advice

Ships to New Zealand

  • Free shipping on orders over $150. Not included: rural addresses and bulky items such as aquariums.
  • Under $150, courier is $6.80 to $9.90 depending on region, or $11.50 to $14.90 for rural addresses. The exact cost shows at checkout.
  • Rural and South Island addresses can take a little longer.
  • Damaged or faulty on arrival? Tell us within 7 days for a replacement or refund.

Full delivery details

Pickup available at Aquascape Shop

Usually ready in 24 hours

Piece size3-8cm

Water
100% aquarium-safe and inert in most freshwater systems

Description

Black Lava Stone is a lightweight volcanic rock prized by aquarists for its porous structure and biological performance. The numerous crevices and internal voids offer abundant surface area for beneficial nitrifying and denitrifying bacteria to colonise, helping maintain water quality naturally.

Its dark, matte finish blends beautifully with driftwood, plants, and other hardscape elements. The stone is easy to stack and “lock” into place, giving you structural stability and creative freedom in your layouts. Over time, biofilm develops over the stone’s surface, offering grazing grounds for shrimp and microfauna.

Features & Benefits

  • Aquarium-safe and inert in most freshwater systems
  • Highly porous surface ideal for beneficial bacteria
  • Natural black/charcoal tones that complement planted aquariums
  • Excellent for aquascaping styles: Iwagumi, nature, mountain, island, etc.
  • Supports biofilm growth — good for shrimp and small aquatic life
  • Two purchase options to suit your design needs

Sizes / How We Sell

  • 2 kg bag (3–8 cm pieces) — well-balanced mix perfect for foreground and midground
  • 10–20 cm pieces (sold per kg) — use as focal or structural stones

Note: Smaller, ultra-porous fragments may float initially. Pre-soak or hold submerged until they saturate, then they will sink.

Preparation & Usage Tips

  1. Rinse stones under clean water to remove dust and debris.
  2. Optionally soak for 24–48 hours before use to ensure full saturation.
  3. In ultra-soft or low-buffer water setups, spot-test a sample rock (check pH/KH before and after) as a best practice.
  4. Use natural layout techniques: wedge smaller stones, stack, tie moss or plants into the crevices, and allow biofilm to mature over time.