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Limewood mini airstones perfect for the Oceanic BioCube protein skimmer.
Oceanic airstones are made of the highest-quality limewood.
Limewood is an extremely durable wood, anatomically composed of a very fine and straight porous grain. Each airstone is specially cut to maximize the number of miniscule air bubbles continuously released through and along the grain of the wood.
The rugged screw-in nipple ensures long life under high-pressure conditions created by today's powerful pumps.