Penn-Plax Aqua-Mist Air Stone Cylinder, Green 12 ct, 0.44 in, 4 ct

If you run more than one tank or simply like to keep spares on hand, the Penn-Plax Aqua-Mist Air Stone Cylinder in a 4-pack is a smart, stock-up choice. This green cylinder air stone measures 7/16 inch (0.44 in), and Penn-Plax describes the air stone as a necessary accessory in most freshwater and saltwater aquariums because it aids in water movement and gas exchange. With a generous count in every order, you'll always have one ready to keep the bubbles flowing. Aeration that's simple and in steady supply makes tank care that much easier.

• Multi-pack count means you can outfit several tanks or keep backups on hand.
• Compact 7/16 inch (0.44 in) cylinders fit neatly into a wide range of setups.
• Green coloring blends into your aquascape while each stone works.
• Penn-Plax says they're a great way to aerate your aquarium.
• Aid in water movement and gas exchange to support a healthier tank.
• Each one hooks up to any aquarium air pump you already own.
• High pore design creates a cascading stream of bubbles inside your aquarium.
• Suited to both freshwater and saltwater aquariums for flexible use.
• Replacements are always within reach, so a worn stone never slows you down.
• A practical, budget-friendly way to keep oxygen flowing across multiple tanks.

For owners juggling several aquariums or anyone who likes to plan ahead, buying these air stones in a 4-pack just makes sense. Connect each green cylinder to an air pump, set it where you'd like the bubbles to rise, and let the high pore design send up that steady cascading stream. When one eventually needs swapping, the next is right there waiting. The Penn-Plax Aqua-Mist green cylinder air stone multi-pack keeps your tanks aerated, your fish breathing easy, and your supply closet ready for whatever your aquariums need next.