Replacement Filters for the Crystal Quest Big Blue Iron/Mn/Sulfide Cartridge Whole-House System
Crystal Quest Big Blue Iron/Mn/Sulfide Cartridge
✅ Best value — replace everything at once
IPW 2-cartridge set — every replaceable stage in one order
✓ Guaranteed to fit your Crystal Quest Big Blue Iron/Mn/Sulfide Cartridge
📋 Typical replacement: sediment every 3–6 months · carbon every 6–12 months · iron/KDF cartridge yearly
1
Sediment pre-filter 5 micron
20×4.5 Big Blue
Replaces OEM 5-micron sediment
2
Iron/Mn/H2S GAC+KDF85 cartridge
20×4.5 Big Blue
Replaces OEM GAC + KDF85 catalytic cartridge
Not sure this is your system? Use the Isopure Water Filter Finder → Match by system name, by the part number on your cartridge, or by photo.
Compatibility reference only. Photos of complete systems shown on this page are provided to help you identify your unit and confirm that our filters fit. All brand names, model numbers, and product images are the property of their respective owners; Isopure Water (IPW Industries Inc.) is not affiliated with, sponsored by, or endorsed by these manufacturers. We sell compatible replacement filters and parts — not the branded systems pictured, unless a system is separately listed for sale on our store.
