Each bag contains 10L unwashed Lava Stone in Medium, 0-10mm particle size.
Lava stone is very effective at creating the ideal living environment for your aquarium as due to its porosity it provides plenty of surface area for beneficial denitrifying bacteria to develop. This beneficial bacteria has the ability to improve water quality by removing nitrates. Shrimp will also forage on Lava stone as small particles of food may become lodged in the millions of open cavities. Lava stone is also extremely popular with cichlid enthusiasts in their tank setups.
Lava stone has an SG greater than 1.0. It does not float in water.