DescriptionThese professional Air Stones are made of sturdy materials, durable and practical, and has a long service life. This is a great way to add oxygen to your aquarium, fish tank, hydroponics and circulatory system. Very suitable for use in fish tanks and aquariums. It will be your good choice.Features-Color:Blue -Material:Ore sand -Size:5.70X5.00X2.00cm/2.24X1.97X0.79in (Sea Star) -Size:9.00X4.00X2.80cm/3.54X1.57X1.10in (Conch) -Size:4.70X4.60X1.50cm/1.85X1.81X0.59in (Shell) - Different style: sea star, sea snail, and shell, optional for use. - Oxygen-increasing effect: the bubble stone can increase the oxygen content in the water, improving the living environment for fish. - Sea Star, sea snail, and shell shape: beautiful and elegant, adding decoration to the fish tank. - Safe materials: made of safe material, safe and reliable. - Easy to install: small in size, easy to install, convenient to use, fish tank bubble stone is a good accessory for air pump.