--Tiny but Enduring: There are 50 aerator stones in the package, Each air stone for aquariums measures 0.6" D x 1" H and weighs 0.3 oz. Tiny but well-constructed for continual bubbling. Washable and reusable. Ideal for small fish tanks or aquariums. --Dense Bubbles: The air stone cylinders produce a good amount of fine and uniform bubbles. A great way to increase oxygen solubility in your aquarium and enliven the aquatic lives. --Reliable Material: Made of mineral material and sintered at a high temperature, it causes no effect to the health of your aquatics. And not much noise. Help keep your fish growing healthily. --Widely applicable: Great for freshwater, saltwater/reef aquariums and hydroponic use; Increase oxygen levels, "blow off" CO2 and raise pH; Can be easily driven by even air pumps --Important: Soak the aerator stones completely in water for 1 hour before use. Clean the fish tank bubbler regularly with a brush as it gets clogged after weeks or months of usage. What Kind of Air Stone Should I Use? A bigger air stone needs a more powerful pump to produce more bubbles. Basically bigger air stones can produce more nice bubbles and they're used for powerful air pumps. If you connect a bigger air stone to a small pump, the bubbles will be produced only at the front of the stone. Small pumps go well with small air stones while powerful pumps and small stones don’t get along well. Makes Lots of Bubbles Aquarium air stones moderate in size and outputs a large steady stream of tiny bubbles, no leaks, add enough oxygen to your fish, and also make your fish tank more beautiful. Air stones extend the life of your nutrient solution, help keep roots healthy, and promote exceptional growth. This stone is a must have for your aquariums. Specifications 1. Material: Silicon carbide, plastic 2. Suitable occasion: fish tank, aquarium, hydroponics and so on Package Included 50 pieces of air stones Notes Note: Please soak the air stone in water for about 30 minutes before first use. If the air stone doesn't have bubbles in one part, please change the pump of higher power. After a long-term usage, please clean it if bubbles lessen.