Ceramic Bio Rings — 1 L Filter Media Bag

Ring-shaped ceramic media with a cut that is porous all the way through, not just on the surface. Water flows through the centre of every ring, and that is where the nitrifying bacteria colony actually lives.

• Porous ceramic, inside and out. The micro-channels give bacteria far more surface than solid sintered glass rings of the same size.
• One litre, loose in the bag. Pour it straight into a media basket, an external canister or the bottom chamber of a hang-on-back filter.
• Goes after mechanical filtration. Sponge or floss first so the rings do not clog with detritus — bio media works best in already-clear water.
• Never replace all of it. When cleaning, rinse half in tank water you have thrown out and put it back. Replacing the whole bag restarts your cycle.