Bio-Cylinder Biological Filter Media 1 kg - IceCap

IceCap's Bio-Cylinder media is built around a simple premise: maximize the surface area available to nitrifying bacteria within a compact, durable form factor. Each three-quarter-inch pellet is a dense arrangement of small ceramic spheres, and that porous ceramic structure is what makes colonization effective. Beneficial bacteria establish deeply within the pellet rather than just on the surface, which translates to more stable biological filtration and better resilience against disruption during routine maintenance.

At 5 gallons of rated capacity per pellet, a single 1 kg box handles systems up to 750 gallons total — making it practical for anything from a small reef tank to a large sump-driven display. The ceramic construction is chemically inert with a neutral pH of 7–7.5, so it won't interfere with water chemistry in either freshwater or marine setups. The media is also rated for pond use, giving it flexibility beyond the typical aquarium application.

Placement options are broad. The pellets can be stacked loosely in a sump, loaded into a canister or wet/dry filter, used in a hang-on-back, or dropped directly into the tank with the included media bag keeping them contained. To accelerate the startup cycle, soaking the media overnight in a bacteria culture before adding it to the system is recommended.

Maintenance is minimal — a light rinse and surface scrub with tank water every 12 months, with full replacement every five years or as the media shows signs of degradation. One important note: never clean or replace all the media at once. Doing so risks crashing the biological filtration by removing the established bacterial colony in a single step. Add or replace incrementally to preserve the cycle.