A WIO first: the rounded expression of the iconic Ryuoh. We introduced Ryuoh in boulder form so you can keep the mountain DNA, deep greys and pale mineral veins, while composing with softness and flow. The result is a stone that reads calm and timeless, perfect for Iwagumi minimalism and convincingly natural river-stream tanks.

Where classic Ryuoh cuts sharp ridges, Ryuoh Boulders are water-shaped: rounded silhouettes, softened seams, and quiet veining that glows under light. Drop a single piece in pale sand and the scene exhales; group a kit and you get meanders, bars, and eddies that feel discovered rather than arranged. Side light draws silvery highlights along the arcs; top light settles everything into a serene, mist-grey hush.

Scaping is effortless when you let “current” lead the composition. Seat one main boulder slightly off-axis to set direction, then nest smaller pieces downstream to create natural banks and resting pockets. Half-bury a few to suggest sorting; leave negative corridors where water would move. For seamless scale transitions, veil the bases with WIO Accents Grey Chips, and echo the language with classic Ryuoh Stones for subtle ridge contrasts that frame the rounded masses.

Function matches beauty. The contours are livestock-friendly; crevices invite moss and epiphytes, use WIO PlantGlue for quick establishment. As a calcareous limestone, Ryuoh Boulders may gently nudge pH and hardness over time, easy to manage with routine soft-water changes or buffering, while you enjoy that unmistakable Ryuoh presence translated into soothing, river-true forms.

• Key Points

  • Color: Deep grey with white marbling and soft transitions.
  • KIT Boulder Sizes: Nano 3–16 cm; Box 3–17 cm; Mega 3–22 cm (typical mix).
  • Texture: Naturally rounded, water-worn faces; soft, sculptural forms.
  • Composition: Natural limestone (calcareous).
  • Matching: Pairs with WIO Grey Chips; complements Ryuoh Stones or contrasting driftwood.
  • Results: Organic flow, gentle valleys, and river-bed realism.
  • Ready to Use: Pre-washed; a quick rinse is optional to clear transit dust.
  • Water Chemistry: Calcareous, may raise pH and hardness over time.
  • Safety: Safe for fish, shrimp, and plants when used as directed.
  • Versatile: Ideal for aquariums, paludariums, and terrariums.
  • Packaging: Boulder Boxes, Nano 5 kg (≤45 cm tanks), Box 11 kg (≤60 cm), Mega 21 kg (≤90 cm). Combine Box+Mega ≈120 cm; 2×Mega ≈150 cm. Main boulder slightly shorter than stones due to bulk (~12–15 cm Nano; 15–20 cm Box; 17–23 cm Mega).
  • Origin: Asia; selected and packed by WIO.
  • Care Level: Easy to Intermediate (due to mineral activity).
  • Why choose this: Choose Ryuoh Boulders when you want Ryuoh’s iconic mineral look in a softer, rounded form, and you’re comfortable managing mineral hardness.

• Usage

  • Pre-wash: Ready to use; brief rinse improves initial clarity.
  • Placement: Seat the main rounded piece first; tuck smaller boulders to form natural banks and channels.
  • Standalone or Mixed: Use alone or combine with Ryuoh Stones and Accents Grey Chips for authentic talus.
  • Decorate & Plant: Contrast smooth forms with fine-leaf plants; use WIO PlantGlue for epiphytes and moss.
  • Filling the Tank: Add water gently; Pro Tip: pour over a plate or décor to protect contours.
  • Final Touch: Skim loose fines; start filtration; light haze clears within hours.
  • Maintenance: Vacuum debris; brush faces with WIO Maintenance Tools if algae appears.
  • Water Parameters (Calcareous): Monitor pH/kH; perform regular changes with osmotic/soft water or use WIO water treatments to control mineral rise.

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