UNS · Stone
Ancient Stone
Iwagumi keepers who like the Manten look and want a slightly darker, more angular stone.
4 models
UNS · Stone
UNS Blue Mountain Seiryu Stone
A darker, medium-grey Seiryu with a blue tinge and pale veins running through it. It gives more contrast than classic Seiryu while keeping the same sharp, grooved character.
Updated
Best for
Iwagumi scapes in hard or moderately hard water that want Seiryu shapes with a cooler colour.
Worth knowing
Hardens water like other Seiryu, which matters for soft-water shrimp.
What stands out
- 5, 10, 20 and 30 lb lots
- Medium-dark grey with blue tinge and light veins
- Classic Seiryu grooves and peaks
- Well priced for a Seiryu variety
Models and specs
| Model | Weight |
|---|---|
| 5 lbBLU0005 | 2.3 kg |
| 10 lbBLU0010 | 4.5 kg |
| 20 lbBLU0020 | 9.1 kg |
| 30 lbBLU0030 | 13.6 kg |
- Brand
- UNS
- Effect on water
- Raises KH, GH and pH (calcareous, like all Seiryu-type stone)
- Colour
- Blue-grey with pale veins
- Texture
- Grooved, jagged
- 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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Budget-friendly builds, nano tanks and moss-covered scapes that need plenty of stone volume.
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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 Blue Mountain Seiryu Stone, drawn from its specs.
Does Blue Mountain Seiryu Stone affect water chemistry?
Raises KH, GH and pH (calcareous, like all Seiryu-type stone).
How do I prepare Blue Mountain Seiryu Stone before use?
Rinse and scrub well before use
Who is the UNS Blue Mountain Seiryu Stone best for?
Iwagumi scapes in hard or moderately hard water that want Seiryu shapes with a cooler colour.
Is there anything to watch out for with the UNS Blue Mountain Seiryu Stone?
Hardens water like other Seiryu, which matters for soft-water shrimp.
What are the alternatives to the UNS Blue Mountain 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.