Clarathon Premium Ultra Filters: the most effective, durable pool & hot tub spa filter cartridges. These blue media filters feature Antimicrobial protection which lasts for the life of the cartridge, & inhibits the growth of bacteria that can foul and weaken a cartridge.
Antimicrobial filters are easier to clean and less prone to odors & staining than ordinary filters. When changing spa water, always rotate the soiled ones out with clean, dry spares. The result is longer filter life and no waiting.