Fluval Plant & Shrimp Stratum
Water type
Freshwater
Fluval Plant & Shrimp Stratum
A volcanic soil substrate that softens water for plants and shrimp without a separate buffer. Fluval Plant & Shrimp Stratum is a porous, active substrate sourced from the foothills of Mount Aso in Japan, built for planted aquascapes and dwarf shrimp colonies.
The granules are lightweight and non-compacting, which lets roots and burrowing shrimp move through the substrate freely, and the porous surface gives beneficial bacteria somewhere to colonise. Fluval states it helps support a neutral to slightly acidic pH and softens water by reducing carbonate hardness — useful for soft-water species without reaching for a separate pH product.
Key features
- Active volcanic soil — porous granules from Mount Aso, Japan, that support root growth and bacterial colonisation.
- Softens and buffers water — helps move water toward neutral-to-slightly-acidic and reduces carbonate hardness, per Fluval.
- Non-compacting — stays loose enough for roots and shrimplets to move through it.
- Shrimplet refuge — the granule structure gives newborn shrimp somewhere to hide until they're large enough to be out in the open.
- Won't discolour water — Fluval notes it also helps control the tannin staining that driftwood can cause.
Specifications
| Spec | Detail |
|---|---|
| Material | Volcanic soil (active substrate) |
| Colour | Dark |
| Water effect | Softens toward neutral–slightly acidic; reduces carbonate hardness (no numeric figure published by Fluval) |
| Preparation | Rinse gently in a colander before use — do not agitate vigorously |
| Suitability | Planted tanks, dwarf shrimp, soft-water tropical fish |
Variant specifications
| Size | SKU |
|---|---|
| 0.8 kg | NAN28 |
| 2 kg | — |
| 4 kg | — |
| 8 kg | — |
Will it fit my tank? / How much do I need?
Fluval publishes a simple formula for Stratum coverage: multiply your tank's footprint in centimetres (length × width) by the substrate depth you want in centimetres, then divide by 1000 — the answer is the weight in kilograms.
| Tank footprint | Stratum needed for a 5 cm layer |
|---|---|
| 30 × 30 cm (nano cube) | ≈ 4.5 kg |
| 60 × 30 cm (2 ft) | ≈ 9 kg |
| 90 × 45 cm (3 ft) | ≈ 20.3 kg |
| 120 × 50 cm (4 ft) | ≈ 30 kg |
These are worked examples at a flat 5 cm depth, using Fluval's own formula — not a Fluval-published table for these exact tanks. Slope the substrate deeper at the back for an aquascape and you'll need more; a flat carpet-only layout needs less. For an exact figure, measure your tank's footprint and apply the formula above, or ask us and we'll work it out for your tank.
Suitable for, and not suitable for
Suitable for planted tanks, aquascapes and dwarf shrimp setups wanting a soft, slightly acidic substrate. Not the right choice if you specifically want a hard, alkaline substrate for African cichlids or livebearers — Stratum works against that water chemistry, not with it.
Care and maintenance
Rinse gently before adding — a light dusting of fines is normal and settles within the first day or two. The pH-softening effect is strongest in the first few months and tapers as the substrate's buffering capacity is used up over time; Fluval does not publish a fixed replacement interval.
Goes well with
Works well under root-feeding plants such as swords and crypts, and alongside a gentle filter intake guard to keep shrimplets safe. Ask us about root tabs if you're planting heavy feeders directly into it.
Warranty and delivery
General Fluval warranty terms apply to any manufacturing defect, in addition to your rights under Australian Consumer Law. Larger bag sizes (4 kg, 8 kg) are heavier parcels — standard parcel freight still applies, but expect a heavier box.
Common questions
Do I need to rinse Stratum before use?
Gently, yes — Fluval recommends rinsing in a colander without heavy agitation to remove dust, rather than a vigorous rinse that would break down the granules.
Will it lower my pH permanently?
The softening effect is real but not permanent or precisely quantified by Fluval — expect it to be strongest early on and to fade as the substrate's buffering capacity is used up.
Can I mix pack sizes to hit an exact weight?
Yes — the four sizes are designed to be combined; use the coverage formula above to work out your total, then combine bags to get close to it.
Is it safe for a shrimp-only tank with no fish?
Yes — it's specifically positioned by Fluval for shrimp tanks, including as a refuge for newborn shrimp.
