Black Lava Gravel 5–7mm Aquarium Substrate | Volcanic Aquascaping GravelCreate a clean, high contrast aquascape with Black Lava Gravel, a natural volcanic substrate sized between 57mm. Its deep black color and porous texture make it ideal for aquariums, planted tanks, and terrariums. This lightweight gravel enhances plant growth while adding depth and a modern look to your setup. Why Choose Black Lava Gravel? Deep black color creates strong contrast in aquascapes 57mm size ideal for substrate and top layers Highly porous