Replacement Filters for the Tier1 20" Big Blue Kit Whole-House System
Tier1 20" Big Blue Kit
✅ Best value — replace everything at once
IPW 3-cartridge set — every replaceable stage in one order
✓ Guaranteed to fit your Tier1 20" Big Blue Kit
📋 Typical replacement: sediment every 3–6 months · carbon every 6–12 months
1
Pleated sediment 20 micron
20×4.5 Big Blue
Replaces OEM (replaces S1-20BB/155305-43)
2
GAC granular carbon
20×4.5 Big Blue
3
Carbon block 0.5 micron
20×4.5 Big Blue
Replaces OEM (replaces CBC-20BB/FLOPLUS-20BB)
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.
