Marina Decorative Aquarium Gravel 2kg Marina Decorative Aquarium Gravel 2kg – Create a colourful aquascape in your aquarium with Marina Decorative Gravel. The gravel is epoxy-coated, which makes the gravel inert and also prevents any adverse effects on water chemistry. Research shows that epoxy-coated gravel also provides an optimum surface for the colonization of beneficial bacteria, which in turn provide biological filtration for clear and also healthy water. The gravel is dust free and is also available in a wide variety of colours. For fresh water aquariums only.