Quick Answer
Replace your shower filter cartridge on the interval specified for your product. ZOOSHEN uses a replaceable-cartridge design so you change the cartridge, not the whole filter. Subscribe to receive cartridges automatically.
Problem
Over time a filter cartridge becomes loaded and less effective. If you wait too long, you lose the benefit you bought the system for.
Product Recommendation
Replacement cartridges are available as a 1-Pack, 2-Pack, or 4-Pack. The 4-Pack offers the best per-cartridge value, and Subscribe & Save reduces the price further.