Also called Black Mountain Seiryu Stone, dark seiryu stone is considered a darker cousin to the seiryu stone. This stone gets is name for its darker grey, almost black color with a hint of a bluish undertone compared to the lighter seiryu stone. It has aggressive and jagged grooves. Its texture and characteristics resemble seiryu stone, making it perfect for getting variety and a good partner for brightly colored aquarium plants. Dark seiryu stones are versatile and can be placed at the bottom of hardscape layouts to mimic the natural environment, as well as for forest-style layouts on sandy bottoms and at the bottom of Iwagumi aquascape layouts. They can bring a natural look to aquariums, pallet boxes, aquariums, reptiles, and amphibian enclosures, creating friendly habitats and providing genuine support for aquatic life.