Black Mini Lava Rock for Aquarium (5kg)
Black Mini Lava Rock for Aquarium (5kg), view 2
Black Mini Lava Rock for Aquarium (5kg), view 3
Black Mini Lava Rock for Aquarium (5kg), view 4

Black Mini Lava Rock for Aquarium - Premium Aquascaping Substrate

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Heavy itemDelivery is priced at checkout by weight and postcode, and isn't part of free delivery. Orders over 25kg can't be sent online, so contact us for a freight quote or pick up in store.
Free pickup in KenwickOpen Tue to Sat, 12pm to 6pm

Complete the scape

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About this product

Natural Black Lava Rock for Stunning Aquascapes

Transform your aquarium into a captivating underwater landscape with our premium Black Mini Lava Rock. This naturally porous volcanic stone creates dramatic contrast against lush green plants while providing essential biological filtration for a thriving aquatic ecosystem.

Why Aquascapers Choose Black Mini Lava Rock

  • Superior Porosity: Naturally porous structure provides exceptional surface area for beneficial bacteria colonization
  • Dramatic Aesthetics: Deep black colour creates stunning visual depth and contrast with aquatic plants
  • pH Neutral: Won't alter water chemistry, safe for all freshwater setups
  • Versatile Hardscape: Perfect for creating caves, slopes, and natural-looking rock formations
  • Plant-Friendly: Ideal anchor points for mosses, anubias, and other epiphytic plants

Premium Quality for Discerning Aquascapers

Each 5kg pack contains carefully selected mini lava rocks that have been cleaned and prepared for immediate use. The irregular shapes and natural texture allow for creative aquascaping while the lightweight nature makes positioning and rearranging effortless.

Whether you're creating an Iwagumi-inspired layout or a lush nature aquarium, this volcanic substrate delivers both form and function. The porous surface becomes a thriving hub for beneficial bacteria, supporting your aquarium's biological filtration while adding striking visual appeal.

Specifications: 5kg pack | Mini size pieces | Natural black volcanic rock | pH neutral | Suitable for freshwater aquariums

Delivery and returns

Free delivery over $100 in WA and $150 elsewhere in Australia. Free pickup from our Kenwick store, Tue to Sat, 12pm to 6pm.

Returns policy

  • 5 stars: 20 (100%)
  • 4 stars: 0 (0%)
  • 3 stars: 0 (0%)
  • 2 stars: 0 (0%)
  • 1 star: 0 (0%)
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N Rix

I have used this to place inside the mesh bags to create a hill for my soil, so now I am ready to plant. This will allow the roots to bond onto. This was hard to find from where I am.. I am so glad to order from you guys.. Thanks again

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Ryan Harris
Incredible biological filtration and stunning look

Black Mini Lava Rock from School of Scape has genuinely impressed me on two fronts. The porous volcanic structure is exceptional for beneficial bacteria colonisation – my tank cycled noticeably faster after adding this rock as part of the hardscape. And aesthetically, the deep black colour creates a gorgeous contrast against the green plants and lighter substrate. Every piece has interesting surface texture and no two are exactly alike. A brilliant product that delivers both function and beauty.

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Hannah Ooi
Perfect for attaching moss – absolutely love it

Attaching moss to Black Mini Lava Rock is an absolute pleasure. The porous, rough surface grabs and holds the moss immediately and within a few weeks it's rooting into the stone naturally. I've built a small moss wall effect using several pieces of this rock in my 60cm aquascape and it looks spectacular. The deep black colour of the rock shows through the moss in places which actually adds visual interest rather than detracting from it. School of Scape delivered great quality and I'll be ordering more.

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Emily Tran
pH neutral – perfect for shrimp and sensitive species

I keep a Caridina shrimp breeding setup and using pH-neutral hardscape is essential. Black Mini Lava Rock doesn't affect water chemistry at all, which makes it ideal for my low pH shrimp tanks. I also use it as an additional surface area for beneficial bacteria which helps keep the water quality pristine. The black colour looks fantastic in a shrimp tank and the shrimp constantly explore the porous surfaces foraging for biofilm. Brilliant product from School of Scape – highly recommended for shrimp keepers.

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Chloe Pham
Great for nano tanks and detailed scapes

The mini sizing of this lava rock is what makes it so useful. Rather than large unwieldy volcanic pieces, these smaller rocks can be arranged precisely in detailed aquascapes. I've used them to create a natural-looking rocky foreground in my 30cm cube and the result is exactly the aesthetic I was going for. The rough porous texture and deep black colour add tremendous character. Combined with some java moss and mini anubias the effect is outstanding. Quality product at a very fair price.

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Tom Richards
Lightweight and easy to work with

One of the great advantages of lava rock compared to denser stones like Seiryu is the weight. Black Mini Lava Rock is light enough to arrange and rearrange easily without the physical effort that heavier hardscape requires. This makes layout work much more flexible – I spent a couple of hours trying different arrangements before settling on the final composition and it was genuinely enjoyable. The deep black colour and porous texture look excellent and the rock has been completely inert in my water. School of Scape quality as always.

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Marcus Bellamy
Excellent surface area for beneficial bacteria

From a biological filtration perspective, Black Mini Lava Rock is exceptional. The naturally porous volcanic structure provides an enormous surface area for beneficial bacteria to colonise compared to smooth rocks of the same size. Since adding a significant quantity to my 90cm tank I've noticed markedly more stable ammonia and nitrite processing. The tank handles bioload spikes much more effectively. And it looks fantastic too – the dark black tones work beautifully with the overall scape aesthetic. Dual function product that truly delivers.

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Daniel Chen
Water stayed crystal clear after adding

I rinsed the Black Mini Lava Rock thoroughly before adding to my tank and experienced zero cloudiness or discolouration. The rock is completely inert and hasn't affected my pH or hardness at all which is exactly what I needed for my softwater planted tank. The aesthetic result is brilliant – the deep black volcanic texture adds a completely different character to the hardscape compared to smoother stones. My Apistogramma pair have claimed the largest piece as their territory which is lovely to watch. Great product.

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Natalie Brennan
Pairs brilliantly with Seiryu Stone

I've combined Black Mini Lava Rock with Dark Seiryu Stone in my aquascape and the two materials complement each other beautifully. The lava rock provides a different texture – more porous and irregular – while the Seiryu brings the angular drama and white veining. Used together they create a multi-dimensional hardscape that feels genuinely natural. Both products from School of Scape are excellent quality and using them together produces results that look like competition-level work. Very pleased with this combination.

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Sophie Lawson
My otocinclus love grazing on the surface

An unexpected bonus of adding Black Mini Lava Rock to my tank is watching how much my otocinclus love it. The porous, rough surface is perfect for the algae and biofilm they naturally graze on, and I regularly see three or four otocats working their way methodically across the rock surfaces. The tank looks fantastic with this dark volcanic texture as part of the hardscape and the fish behaviour it encourages adds real life to the overall display. Brilliant product that benefits both aesthetics and the ecosystem.

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Liam Sutherland
Excellent value for a premium volcanic product

At $25 for 5kg of premium Black Mini Lava Rock this is genuinely excellent value. The quantity is generous and gives you plenty of material to work with across a mid-sized aquascape. Every piece had interesting surface texture and consistent deep black colouration. The porous structure is immediately apparent when you handle the rocks – lightweight, with clearly visible micro-pores throughout the surface. School of Scape packed everything securely and delivery was fast. Will be a regular purchase for my builds.

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James Holloway
Creates incredible natural caves for fish

Using multiple pieces of Black Mini Lava Rock I was able to create a natural cave formation in my cichlid tank that the fish immediately claimed as territory. The irregular shapes and varied sizes of the pieces allow you to stack and lean them against each other to form stable cave structures. The deep black colour makes the cave interiors look dark and natural, which is exactly what territorial cichlids want. The rock itself is fish-safe and pH neutral. Excellent versatile hardscape from School of Scape.

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Priya Mehta
Instantly adds natural character to any tank

There's something about volcanic lava rock that just looks inherently natural in an aquarium – more so than any smooth or polished stone. Black Mini Lava Rock from School of Scape has this quality in abundance. Every piece looks like it belongs in a natural underwater environment. The deep black with slightly rusted undertones in places is particularly authentic. My community tank looks completely transformed since adding this hardscape and visitors always ask what type of rock it is. Brilliant product.

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Zoe Hartley
Brilliant for biotope aquascapes

I'm building a West African biotope and Black Mini Lava Rock is a key component of the hardscape. The volcanic stone is authentic to the rocky riverbeds found in many African biotope habitats and the irregular porous surface looks perfectly natural. Combined with some fine sand substrate and appropriate plants the tank is really starting to look like a slice of a real African river environment. School of Scape's lava rock is good quality and the mini sizing is ideal for creating detailed rockwork in a biotope setup.

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Nathan Blackwood
No tannin leaching – water stayed perfect

Unlike some driftwood and certain stones, Black Mini Lava Rock has zero impact on water colour. My water remained crystal clear from day one and I haven't had to adjust any parameters since adding it to the tank. For aquascapers who want dramatic dark hardscape without the water chemistry complications, this is the ideal choice. The rock is completely inert and aquarium-safe. Combined with the superb porous texture and deep black colour it's just an excellent all-round hardscape material. Very pleased.

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Emma Davidson
Makes anubias attachment incredibly easy

Attaching Anubias and Bucephalandra to Black Mini Lava Rock using aquascaping glue is one of the easiest and most rewarding things in this hobby. The porous rough surface grips the glue instantly and the plants root into the rock naturally within a few weeks. I've created several small anubias-covered rock clusters that look like natural underwater plant formations. The dark rock colour contrasts beautifully with the deep green Anubias leaves. A perfect combination – both products from School of Scape of course.

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Ryan Harris
Ordered twice – consistently excellent quality

My second order of Black Mini Lava Rock from School of Scape and the quality has been identical both times. Consistent deep black colour, excellent porosity, good range of sizes, and completely inert in the water. This is now a standard component in my hardscape toolkit that I use across multiple tank builds. The biological filtration benefit alone makes it worth including and the aesthetic contribution is a bonus on top of that. A reliable, versatile, and beautiful hardscape material. Strongly recommended.

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Marcus Bellamy
Beginners and pros alike will love this

Whether you're setting up your first planted tank or your twentieth competition build, Black Mini Lava Rock is a brilliant hardscape choice. It's easy to work with, forgiving in terms of water chemistry, and delivers a beautiful natural aesthetic that suits every style from minimalist Iwagumi to dense jungle scapes. The School of Scape 5kg bag gives you plenty to work with and the quality is consistently good. I've recommended this to several beginner friends and they've all had great experiences with it.

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Hannah Ooi
The black colour never fades

I've had Black Mini Lava Rock in my tank for eight months now and the deep black colour is exactly the same as the day I added it. Some stones and substrates fade or discolour over time but this volcanic rock is as dark and striking as ever. The porous surface has a nice coating of beneficial bacteria and some fine green algae growth in lighter areas which actually looks very natural. This is a long-term investment in hardscape quality and School of Scape has delivered excellent value for money.

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Chloe Pham
Transformed my freshwater planted tank completely

I rebuilt my 60cm planted tank around Black Mini Lava Rock as the primary hardscape and the transformation from my previous smooth river pebble setup is extraordinary. The porous black volcanic texture gives the tank a completely different energy – more dramatic, more natural, more interesting. Every rock has character and the combined arrangement creates depth and shadow that the smooth pebbles never achieved. School of Scape's quality and packaging were excellent. This is now my preferred hardscape material for planted tank builds.