vidaXL Volcanic Rocks 25 kg Black 10-30 cm

The volcanic rocks are a perfect addition to the bottom of your fish tank or aquarium, helping you create a beautiful underwater world! Natural material: The volcanic lava rocks are 100% natural and safe which won鈥檛 affect water's pH or chemistry and are suitable for both fresh and saltwater environments. Decoration: With beautiful natural shaping, the lava rocks provide a colourful and detailed focal feature to your fish tank or aquarium. Biological filter: These volcanic stones make for great natural biological filters that improve water quality, boost oxygen levels, and control nitrates for a cleaner and healthier habitat. Wide applications: The volcanic rocks are also suitable for garden landscapes, planter beds, and other landscaping rock applications.