Whole House Filter | 3 Stage | Big Blue | Stainless | WM

A 3-stage Big Blue whole-house water filter housed inside a SUS304 stainless steel cabinet with a lockable access door — the premium tier in the residential whole-house range, built for visible installations and exposed locations where the standard plastic-housing systems would weather poorly or get tampered with.

Why a Stainless Steel Cabinet

Standard whole-house systems mount the filter housings exposed on a wall or frame. That works fine for a garage or under-house installation, but on properties where the system sits on an external wall, in a carport, or anywhere visible from the street, two problems show up:

• Australian sun and weather — UV degrades plastic housings and brackets over years. White-coated metal frames rust at coastal sites. The filter cartridges themselves are fine, but the system around them ages visibly.
• Tampering and curiosity — accessible filter housings in a visible location invite kids, vandals, or service contractors who shouldn't be touching the system.

The SUS304 stainless steel cabinet solves both. The chromium-nickel alloy is UV-stable, salt-air resistant, and has the self-renewing protective layer that defines stainless. The lockable access door means only people with the key open the cabinet — service the cartridges, then lock it again.

Three-Stage Filtration

• Stage 1 — 5 micron PP sediment cartridge: removes silt, dirt, sand, rust before the carbon stages
• Stage 2 — 5 micron granular activated carbon (GAC): bulk reduction of chlorine and organic contaminants
• Stage 3 — 5 micron coconut-shell carbon block: secondary polish; coconut carbon has higher surface area than coal-based for better chemical adsorption capacity

All cartridges Big Blue 20" × 4.5" — the standard whole-house format. Replacements are widely stocked and not proprietary to this enclosure.

Where This Tier Fits

• This system ($1,300): SUS304 stainless cabinet, lockable, 3-stage Big Blue
• Premium 3-stage Big Blue ($599): same 3-stage filtration, white-coated metal frame, no enclosed cabinet
• WaterMark-certified 3-stage ($1,199.95): same 3-stage build but the Big Blue WaterMark system is the WaterMark-certified option for mains-connected installations where compliance matters

The stainless cabinet adds visual and physical protection — it does not add WaterMark certification.

Installation

Professional installation recommended. Mounts to an external or internal wall at the point of entry. 1" inlet and outlet connections match standard Australian mains supply line.