CHF-Compatible RO Annual Filter Kit

A full year of filtration in one box. Fitted by you in ten minutes.

Three cartridges — everything your alkalising reverse osmosis system needs for twelve months. Delivered free anywhere in Australia. No callout fee, no appointment, no waiting for someone to knock on your door.

Stage 1 — 5 micron sediment. Catches sand, silt, rust and scale flakes shed by pipework before they reach anything finer. Unglamorous work, and the reason the rest of the system lasts.

Stage 2 — coconut carbon block. Reduces chlorine, taste, odour and trihalomethanes. Chlorine degrades the polyamide film an RO membrane is made from, so this cartridge protects your most expensive component as well as improving how the water tastes. Skipping a carbon change is the most expensive saving available in a filtration system.

Stage 3 — alkalising remineraliser. Reverse osmosis strips out the dissolved minerals that give water its taste, leaving it clean but flat and slightly acidic. This cartridge dissolves them back in — predominantly calcium, with trace magnesium and potassium — lifting the water to a steady neutral-to-weakly-alkaline character, then polishes through coconut carbon. It's deliberately a middle point: not flat RO water, not heavily alkalised water.

Why the alkalising stage needs RO in front of it. The mineral media only dissolves into mildly acidic water — which is exactly what RO water is. On ordinary mains water, which usually sits above pH 7, it would barely dissolve at all. That's the design: this cartridge belongs after a membrane. One tip — draw water at a modest rate rather than flat out; slower flow means more contact time and better mineral pickup.

Why replace all three together. The stages work as a chain — a blocked sediment cartridge starves the carbon, spent carbon exposes the membrane, and depleted mineral media leaves the water flat. One job, once a year.

Specifications:

• Stage 1: 5 micron polyspun polypropylene, 10" × 2.5"
• Stage 2: Coconut shell carbon block, 10" × 2.5"
• Stage 3: Calcium-based mineral media with trace magnesium and potassium, plus coconut carbon — 11" × 2.5", 5 micron, ¼" push-fit
• Typical stage 3 output: neutral to weakly alkaline
• Stage 3 flow rate: up to 3 L/min
• Replacement interval: 12 months, normal household use
• Fits: RO systems using 10" × 2.5" pre-filters with an 11" × 2.5" push-fit alkalising stage
• Delivery: free, Australia-wide

Membrane not included — replaced every two years, sold separately.

Compatible aftermarket product by ProperWater — not manufactured by or affiliated with Complete Home Filtration.