UNS · Stone
Ancient Stone
Iwagumi keepers who like the Manten look and want a slightly darker, more angular stone.
4 models
UNS · Stone
UNS Flat Bottom Seiryu Stone
Seiryu formations cut with a flat base so they stand upright on their own. They give an instant Iwagumi-style centrepiece, and several can be grouped in larger tanks.
Updated
Best for
Small cube Iwagumi builds where you want a stable peak without fiddling (S suits 25 cm cubes, M suits 30 cm cubes).
Worth knowing
Raises KH and pH like any Seiryu.
What stands out
- Two sizes, about 19 cm and 28 cm tall
- Flat-cut base for easy, stable placement
- Classic grey Seiryu grooves and peaks
- Can poke above the waterline in small tanks
Models and specs
| Model | Dimensions (L × W × H) |
|---|---|
| SFBSS201A | 19.1 × 11.4 × 19.1 cm |
| MFBSS201B | 27.9 × 12.7 × 27.9 cm |
- Brand
- UNS
- Effect on water
- Raises KH, GH and pH (calcareous, like all Seiryu-type stone)
- Colour
- Classic Seiryu grey
- Texture
- Jagged, grooved
- Origin
- China
- Prep
- Rinse and scrub well before use
Figures from Glass Aqua's product listing. Makers revise products, so check the current figures before buying. Photos supplied by the brand or its distributor.
What seiryu stone does to your water
It contains calcium carbonate, so it dissolves slowly and pushes pH and general hardness up over time. The effect is stronger in soft, low-buffered water. If you are aiming for a soft-water shrimp or blackwater tank, seiryu will fight you; for a harder community it is fine. Test with a drop of acid, it fizzes.
Full Seiryu Stone guideCompare with
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Shrimp and nano tanks that need hiding spots, or scapers wanting planted pockets at different heights.
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Frequently asked questions
Quick answers about the UNS Flat Bottom Seiryu Stone, drawn from its specs.
Does Flat Bottom Seiryu Stone affect water chemistry?
Raises KH, GH and pH (calcareous, like all Seiryu-type stone).
How do I prepare Flat Bottom Seiryu Stone before use?
Rinse and scrub well before use
Who is the UNS Flat Bottom Seiryu Stone best for?
Small cube Iwagumi builds where you want a stable peak without fiddling (S suits 25 cm cubes, M suits 30 cm cubes).
Is there anything to watch out for with the UNS Flat Bottom Seiryu Stone?
Raises KH and pH like any Seiryu.
What are the alternatives to the UNS Flat Bottom Seiryu Stone?
Other hardscape worth comparing: UNS Ancient Stone, UNS Ashen Stone, UNS Black Lava Rock. Add any of them to the compare table to see the specs side by side.