Seiryu Stone Effects on Water Chemistry
"When using rocks in aquascaping you need to be aware of the effects they can have on chemistry. Many stones contain carbonates, acids, and other elements that will cause minor to dramatic shifts in water chemistry.
Fish, plants, and invertebrates can be sickened or even killed with the wrong stone. As a very general rule of thumb, igneous rocks like granite tend to be inert while sedimentary and metamorphic rocks like limestone and marble tend to affect water chemistry somewhat.
Seiryu Stone, a metamorphic rock, is a bit troublesome because it has a strong effect on the pH of aquariums. To be precise, it contains calcium carbonate, both of which impact the GH (Calcium/Magnesium concentration) and KH (carbonate concentration) of an aquarium.
Taken together you’ll see an increase in pH and water hardness using this rock.
While neutral water in equilibrium with atmospheric CO2 (a weak acid) will show a slow increase in pH the various tannins and other molecules in most aquariums will accelerate leaching of calcium carbonate from Seiryu Stone.
Many fish, such as Livebearers and Rift Lake Cichlids, actually prefer hard water so the alkaline inducing effects of Seiryu Stone can be seen as a bonus."
