It is natural river gravel. Unlike sea gravel, you do not have to worry about hardness increase.
There are 4 size variety, S, M, L, and LL. S size can also be used as substrate material like Oiso sand. M-LL size can be mixed together, and used for promoting riverbed aquascape.
Aqua Soil-Amazonia Ver.2
Amazonia Ver.2 uses black soil for a raw material and it stands out against the leaf color of aquatic plants, and also includes Amazonia Supplement to enrich nutrients. By adding an appropriate amount of Amazonia supplement and laying Amazonia Ver.2, aquatic plants grow better and a beautiful Nature Aquarium can be realized. In addition, natural soils make the water quality suitable for aquatic plants and tropical fish, and it is easy to maintain an aquarium at the initial stage, so it can be used widely from beginners to veterans.
This hardness is free shrimp gravel water neutral, light and CO2 resistant. It is used fish-keeping. The gravel is rounded and has a grain size of 0.7 to 1.2 mm.
Pollutant-free shrimp gravel with rounded grains for a minimal risk of injury. Does not change the water values due to its water-neutral and CO2 resistant texture.