Package contents: the pack contains aquarium sand specially selected to recreate a natural seabed Non-toxic: thanks to this natural substrate, you can safely set up your aquariums, the product is dyed with natural pigments, does not release carbonates and is therefore non-toxic to fish, invertebrates and plants Instructions for use: apply a straightening layer of 4 cm on the front and 7 cm on the back to create a slope that gives depth to the view of the pool Grain size: the sand has a thickness of 2-3 mm, its rounded grains are also safe for fish who like to dig in the ground, such as Corydoras. Size: 10 kg SUITABLE FOR: Sweet and saltwater aquariums