Reverse Osmosis Water Filters NZ

Reverse osmosis water filters for New Zealand homes

Reverse osmosis is the only home water filter that reliably removes fluoride and nitrates. Water is pushed through a semi-permeable membrane with pores so fine that fluoride, nitrates, heavy metals, PFAS, chlorine and up to 99.9% of dissolved solids are left behind. If you're on a fluoridated council supply, in a Canterbury or Waikato nitrate zone, or making up baby formula, an RO water filter is the right system.

Under sink or benchtop RO?

RO Mineral+ (under sink) Smart RO (benchtop)
Install Plumbed in, dedicated tap Plug in, no plumbing
Removes Fluoride, nitrates, PFAS, heavy metals, chlorine, 99.9% of dissolved solids Same membrane, same removal
Minerals Calcium and magnesium added back, light alkaline pH Remineralised
Hot water No Yes — dispenses hot or ambient
Best for Families, owner-occupiers, maximum protection from the kitchen tap Renters, offices, baches, anyone who can't plumb
Price $1,449 $2,249

Both are tested on NZ tap water at an IANZ-accredited lab, carry a 5-year manufacturer warranty and a 30-day money-back guarantee, and ship free in NZ over $200.

What a reverse osmosis system removes

  • Fluoride — added to most NZ council supplies; RO removes the large majority of it
  • Nitrates — from farm run-off into groundwater; a growing concern across Canterbury, Waikato, Southland and Hawke's Bay
  • PFAS (forever chemicals), lead, arsenic and other heavy metals
  • Chlorine and chloramine, taste and odour
  • Microplastics, bacteria, cysts — the membrane is far finer than any of them

What RO also removes is minerals. Plain RO water tastes flat and sits slightly acidic. That's why both our systems put calcium and magnesium back in a final remineralisation stage.

Replacement cartridges

Yearly cartridge sets keep the membrane and mineral stage performing: RO Mineral+ replacement cartridges or auto-delivery and save 10%; for the benchtop unit, the Smart RO SC cartridge and FCR membrane.

Reverse osmosis FAQs

Does reverse osmosis remove fluoride?
Yes. RO is one of the few home methods that reliably removes fluoride, along with nitrates.

Does a reverse osmosis system waste water?
Traditional RO sends three to four litres to drain for every litre filtered. Ours runs the other way: around 4 litres filtered for every 1 litre to waste. The waste goes to the sink drain via a saddle fitting — no tank or pump needed with the RO Mineral+.

Is RO water bad for you because it removes minerals?
Most dietary minerals come from food, not water, but RO water does taste flat. The RO Mineral+ adds calcium and magnesium back so the water tastes right and sits at a light alkaline pH.

How much does a reverse osmosis water filter cost in NZ?
From $1,449 for a plumbed-in under sink system, or $2,249 for a benchtop unit with no installation. Cartridges are around $265 a year.

Do I need a plumber?
For the RO Mineral+, yes — fixed-rate install can be added at checkout. The Smart RO benchtop needs no plumbing at all.