Whole House Water Filter | 3 Stage | 20" x 4.5" | Replacement Set
SKU: EA-WF-WH-3S
Ships free Australia-wide. Delivered by Allied Express or Aramex bulky freight, 3–10 business days depending on state.
Free Click & Collect from our Wyong NSW showroom (in stock for immediate pickup).
Same-day dispatch on orders before 12pm AEST.
In stock.In stock · ships from Wyong, NSW
Order today for fast dispatch
14-day returns on damaged or faulty items — returns policy
Questions? Call (02) 8772 8162 Mon–Thu 9am–3pm
- Set contents
- 3 cartridges
- Cartridge format
- Big Blue 20" × 4.5"
- Micron rating
- 5 micron
- Service interval
- 6–12 months
Specifications
- Set contents
- 3 cartridges covering 3-stage filtration
- Cartridge format
- Big Blue 20" × 4.5"
- Stage 1
- 5 micron sediment
- Stage 2
- Carbon
- Stage 3
- 5 micron polish
- Recommended service interval
- 6–12 months per cartridge
- Compatible housings
- 20" × 4.5" Big Blue (not interchangeable with 20" × 2.5")
A 3-cartridge replacement set sized for 20" × 4.5" Big Blue whole-house filter systems — the standard whole-house cartridge format used across the Australian residential filter market. One SKU covers a complete service refresh on any standard 3-stage Big Blue installation.
What's in the Set
- Stage 1 — 5 micron sediment cartridge: removes silt, dirt, sand, rust
- Stage 2 — Carbon cartridge: bulk chlorine and chemical contaminant reduction
- Stage 3 — 5 micron polish cartridge: finer chemical and chlorine polish
All cartridges 20" × 4.5" Big Blue format.
Service Interval
Approximately 6–12 months per cartridge under typical Australian town water conditions. Properties on heavier sediment loads (rural tank, bore water with iron content) may need more frequent changes. The premium 3-stage Big Blue systems with built-in pressure gauges take the timing guesswork out — the pressure differential between inlet and outlet signals when replacement is due.
Compatible Systems
Fits the full Big Blue 20" × 4.5" 3-stage range:
- Premium 3-stage Big Blue with pressure gauges
- WaterMark-certified 3-stage Big Blue
- Deluxe stainless steel lockable 3-stage Big Blue
- Any third-party 20" × 4.5" Big Blue 3-stage system using standard cartridge format
Note: 20" × 4.5" cartridges are not interchangeable with 20" × 2.5" cartridges. Confirm your housing diameter before ordering — the slimmer 2.5" format uses the 20" × 2.5" 3-stage set instead.
Key features
- 3-cartridge replacement set for Big Blue 20" × 4.5" whole-house systems
- 5 micron sediment + carbon + polish across the three stages
- Fits premium, WaterMark, and deluxe stainless 3-stage Big Blue ranges
- Approximately 6–12 month service interval per cartridge
- One SKU covers a complete annual service refresh
- Big Blue 20" × 4.5" — Australian whole-house standard format
Recommended for
- Annual or biannual service of a 3-stage Big Blue whole-house system
- Owners of premium, WaterMark, or deluxe stainless 3-stage Big Blue installations
- Plumbers stocking Big Blue consumables for service jobs
- Replacement after a missed service interval or system handover
Compliance & certification
Replacement cartridge set — not subject to WaterMark certification.
Ready to order?
Order before 12:00pm AEST on a business day for same-day dispatch from Wyong NSW. See shipping details.
Frequently bought together
More whole house
What customers say
5.0 from 74 customer reviews
- Google
“Just discovered this place. Huge variety of stock. Prices are excellent. Service top notch. My new go-to place for all things water filters.”
- Facebook
“Brilliant — everything supplied including pressure limiting valve. Very easy to fit. Best water ever. Best service and communication with the supplier.”
Australian-owned
Real Wyong NSW warehouse and showroom. ABN 24 638 197 734. Proper tax invoices on every order.
Same-day dispatch
Orders placed before 12pm AEST on a business day ship the same day from Wyong. Tracked Australia-wide.
No proprietary lock-in
Standard 10" and 20" Australian housings. Buy replacement cartridges from any supplier.
Whole House Water Filter | 3 Stage | 20" x 4.5" | Replacement Set
$1,149.95 AUD