WIO > Dragon Stone
Dragon stone is the pitted, cratered, honeycombed rock that has been the backbone of planted aquascaping for twenty years — and WIO's take on it comes in two named tones, Dark Knight and Hulk, at 12 kg per box.
Why this texture became the standard
Dragon stone's appeal is not the color, it is the surface. The deep pits and hollows do three useful things at once: they read as weathered and ancient at any scale, they cast their own shadows so the rock has depth under flat aquarium lighting, and they give you a hundred places to wedge moss, anubias and bucephalandra without glue.
That last point is the practical one. Plant a dragon stone scape and within a few months the plants have colonized the crevices and the rock looks like it grew there. Smooth stone never does that — anything you attach sits obviously on the surface.
Dark Knight and Hulk
Dark Knight is the darker, cooler tone. Strong contrast against green planting, and it recedes visually, which makes a scape look deeper. Good with pale substrate.
Hulk is the warmer, greener-toned option. Softer contrast, more naturalistic, and it sits more comfortably in a heavily planted tank where you want the rock to belong rather than to dominate.
Both come as graded assortments in a 12 kg box — a dominant piece with supporting stones from the same batch, which is exactly what you want and exactly what buying rock piece by piece over several months fails to give you.
Building with it
Dragon stone suits stacked, layered layouts. Set the largest piece off-center, tilt it, and build outward with the pitted faces turned toward the viewer — the texture is the whole point and it disappears if you bury the interesting side.
Keep the strata direction consistent across pieces. The commonest amateur error with this stone is treating each rock as an independent object; the commonest professional move is making six rocks look like one broken formation.
Leave the crevices accessible. You will want them later for planting.
A real caution about crumbling
Dragon stone is comparatively soft and it sheds. Expect fine clay-colored dust when you handle it, and expect some when it first goes under water. Rinse and gently scrub each piece before it goes in, and be prepared for a day or two of slight haze afterwards.
It also means the stone is fragile at thin edges. Do not lever pieces against each other, and do not build an unstable stack that depends on a narrow point of contact — it can give way weeks later.
Chemistry
Traditional Ohko-type dragon stone is a clay-based material and generally considered inert. WIO publishes no data for these specific stones, so do not take that as read for these. The vinegar test settles it: a drop on a dry surface, fizzing means carbonate content that will raise KH and pH over time, no reaction means inert.
It matters most for Caridina shrimp, wild bettas and soft-water breeding, and least for community tanks on San Diego's already-hard tap. Full explanation on our aquascaping stones page.
What to plant on it
Anubias nana petite, bucephalandra, mini christmas moss and java fern — all rhizome plants that must be attached rather than buried. Tuck the rhizome into a crevice or glue it with cyanoacrylate gel, and never bury it or it rots. See layout material for thread and plant glue, and aquarium plants for the plants themselves.
Pick your pieces in person
Every box is different and the shapes decide your layout. Come and look at what is on the floor at Convoy, lay a few out, and take the ones that talk to each other. Free water testing while you are in. See also the rest of the WIO stone range.