Oase Indoor Aquatics Hel-X 13 BioMedia Replacement Filter Media for all BioMaster Aquarium Filters

OASE Hel-X 13 BioMedia – A 0.3-gallon pack of advanced biological filter media for OASE BioMaster filters. The Hel-X 13 media consists of small helix-shaped plastic pieces with an extremely high surface area, providing an ideal environment for beneficial bacteria to colonize. By enhancing biological filtration, this media helps break down ammonia and nitrite, contributing to a healthier, balanced aquarium ecosystem (replace or rinse only when necessary to preserve beneficial bacteria).