Aquael Basalt Gravel 2-4mm 2kg - Natural Black Volcanic Rock for Aquariums, Terrariums & Planted Tanks - Perfect for Fish Tank Decoration & Plant Substrate

BASALT GRAVEL is ideal for aquariums inhabited by timid fish that prefer dark substrates; a comprehensive range of substrates natural and safe (do not damage fish) do not affect water chemistry (except for the deliberate action of dolomite gravel) suitable for all types of freshwater aquariums.