Activ Betta Gems 1LB (Grain size: 3.1 -4.7mm)Premium All Natural LIVE Substrate Specially Packaged in LIVE Fresh Water For Instant Cycling Of Your Betta Aquarium and Fresh Water Fish Aquariums. Use them in your aquariums and ponds to make the floor bottom look great. It provides living space for beneficial microbes and anchoring for plants. It helps with the filtering process of the water in your aquarium tank or pond.