Fish Gear Aquarium Glass Gems. Gravel is an essential part of an aquarium that assists in mechanical and biological filtration, leading to a healthier and happier fish environment. Fish Gear gravel helps prevent food, fecal mater, and other debris from freely floating around the aquarium. Fish Gear gravel also comes in a variety of designs and colours to add fun and beauty to any style of aquarium. Enhance your finned friend's home today with Petland Fish Gear Gravel! Suitable for a betta home or to add a splash of colour to your aquarium 100% safe & non toxic Available Size: 500 g Container Directions: Rinse gravel THOUROUGHLY with cold water until water runs clear and free of debris and colour. (Never use soap or detergent) When filling your tank with water, place saucer on gravel and pour water onto the saucer. This will help prevent the water from disturbing your new gravel. Once your aquarium is set-up and running, use a gravel vacuum for regular aquarium cleaning.