Package contents: base material for freshwater aquariums, specially selected decorative substrate to replicate the bottom of aquariums Natural: with this natural sand, you can set up your aquariums safely. Non-toxic, does not release carbonates Usage: Arrange a directional layer of 4 cm at the front and 7 cm at the back to create a gradient that adds depth to the view of the tank Grain: ultra-fine 1-3 mm Format: 700g