Under Sink Reverse Osmosis Water Filter Systems for South African Homes
An under sink reverse osmosis water filter removes up to 99% of contaminants using five to eight filtration stages, a 10 to 12 litre storage tank, and a dedicated chrome faucet at the kitchen sink. In South Africa, an under sink reverse osmosis water filter typically costs between R1,999 and R11,000, depending on stage count and whether a booster pump is included.
Key Takeaways for an Under Sink Reverse Osmosis Water Filter
- A six-stage under sink reverse osmosis water filter removes bacteria, fluoride, heavy metals and dissolved salts.
- South African prices range from around R1,999 to R11,000, depending on stage count.
- Pressure below 3 bar usually needs a booster pump fitted for reliable flow.
- Pre-filters need replacing every 6 to 12 months; the membrane lasts 2 to 3 years.
- Little Luxury Water Filters stocks complete systems, cartridges and maintenance products.
How an Under Sink Reverse Osmosis Water Filter Works
Water entering an under sink reverse osmosis water filter passes through a sediment cartridge, then carbon stages that strip out chlorine and odour, building on the basic principle behind any device designed to strip impurities from drinking water. The membrane then blocks bacteria, fluoride and dissolved salts down to 0.0001 micron, and a final mineral stage restores calcium, magnesium and potassium for a taste closer to spring water.
What Does Reverse Osmosis Remove From Water?
- Bacteria, protozoa and viruses
- Fluoride, chlorine and chloramine
- Lead, arsenic, copper and chromium
- Dissolved salts, calcium and magnesium
Choosing the Right Under Sink Reverse Osmosis Water Filter for Your Home
Little Luxury Water Filters' 6-Stage Reverse Osmosis Water Filter System pairs a 12 litre pre-pressurised tank with a goose neck faucet, so filtered water stays on tap without running the membrane continuously. The replacement set below swaps out all six stages once the originals reach the end of their working life.
6-Stage Reverse Osmosis Water Filter System
R1,999.00A complete six-stage under sink reverse osmosis water filter with a 12 litre pre-pressurised tank and goose neck faucet, giving continuous access to filtered water.
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6-Stage RO Replacement Filter Cartridge Set
R999.00A full set of six replacement cartridges, covering the sediment, carbon, membrane and mineral stages of an existing system.
View ProductLittle Luxury Water Filters also stocks the Platinum Complete range for a no-drill alternative to a full reverse osmosis installation. Its three-stage carbon block filtration removes up to 99% of contaminants while keeping beneficial minerals.
Platinum Complete Under Sink Water Filtration System
R2,599.00A three-stage, NSF-certified system with a core-filter design, so only the inner cartridge needs replacing.
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Platinum Complete Replacement Filter Cartridge
R1,299.00A two-stage sediment and carbon block cartridge lasting up to a year, for the Platinum Complete system.
View ProductFor homeowners comparing options, Little Luxury Water Filters' full range of water filtration systems covers everything from countertop units to complete under sink reverse osmosis water filter installations.
Water Pressure and Booster Pumps for Under Sink Reverse Osmosis Water Filter Systems
Reverse osmosis membranes need enough incoming pressure to work efficiently. Pressure below 3 bar generally needs a booster pump fitted, while pressure above 5.5 bar calls for a pressure-reducing valve, since excess pressure shortens the membrane's lifespan. The membrane also sends a portion of incoming water to the drain, and an auto-shutoff valve stops the system drawing more once the storage tank is full.
Under Sink Reverse Osmosis Water Filter vs Whole House Filtration
An under sink reverse osmosis water filter treats water at a single point, usually the kitchen tap, for the highest purification of drinking water. A whole house system filters water as it enters the property instead, so every tap and appliance receives treated water. Households drawing from a borehole water filters in South Africa supply often pair the two approaches.
Water-Stream Whole House System, Advanced
R40,000.00A high-flow commercial-grade valve system rated to 150 psi, suited to larger properties with heavier contamination. Qualified plumbers receive a 20% discount.
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Water-Stream Whole House System, Standard
R25,000.00A standard-capacity model from the same commercial range, suited to smaller commercial or larger residential properties.
View ProductMaintaining Your Under Sink Reverse Osmosis Water Filter
Sediment and carbon pre-filters need changing every 6 to 12 months, while the membrane lasts 2 to 3 years. Between changes, residue and mineral deposits can still build up inside the filter housings.
Water Filter Housing Cleanser
R169.00Clears residue and mineral build-up from filter housings and sanitises the chamber between cartridge changes, for cleaner, better-tasting water.
View ProductFor a full record of costs across a system's lifetime, Little Luxury Water Filters' guide to water filter system for home prices breaks down what to budget for year on year.
Comparing Little Luxury Water Filtration Systems
| Product | Stages | Price (ZAR) | Best For |
|---|---|---|---|
| 6-Stage Reverse Osmosis Water Filter System | 6 | R1,999.00 | Under sink drinking water |
| 6-Stage RO Replacement Filter Cartridge Set | 6 | R999.00 | Cartridge replacement |
| Platinum Complete Under Sink Water Filtration System | 3 | R2,599.00 | No-drill under sink filtration |
| Platinum Complete Replacement Filter Cartridge | 2 | R1,299.00 | Platinum cartridge replacement |
| Water Filter Housing Cleanser | – | R169.00 | Housing maintenance |
| Water-Stream System (standard model) | Commercial valve | R25,000.00 | Larger properties |
| Water-Stream System (high-capacity model) | Commercial valve | R40,000.00 | Commercial premises |
Price Comparison: Everyday Filtration Products
The Water-Stream commercial range (R25,000.00 to R40,000.00) is shown separately in the table above.
Frequently Asked Questions
How much does an under sink reverse osmosis water filter cost in South Africa?
A complete six-stage reverse osmosis system from Little Luxury Water Filters costs R1,999.00, with a replacement cartridge set at R999.00. The 3-stage Platinum Complete system costs R2,599.00 for a simpler, no-drill alternative.
How many filtration stages does an under sink reverse osmosis system need?
Most households do well with six stages: sediment, two carbon stages, the membrane, a polishing cartridge and a mineral stage. Boreholes and older plumbing benefit most from the full six.
Do under sink reverse osmosis systems need a booster pump?
Only where incoming pressure falls below 3 bar. Homes on strong municipal supply rarely need one, while weak or fluctuating pressure calls for one to keep the membrane working efficiently.
How often should the filters be replaced?
Sediment and carbon pre-filters generally need replacing every 6 to 12 months, and the membrane lasts 2 to 3 years, depending on water quality and household usage.
Can I install an under sink reverse osmosis water filter myself?
The system is DIY-friendly, and many customers fit it themselves using the included wrenches and tubing. Little Luxury Water Filters still recommends professional installation where incoming pressure needs adjusting, to protect the warranty.
Does reverse osmosis remove healthy minerals from drinking water?
Yes, the membrane strips out calcium, magnesium and other minerals along with contaminants. A post-mineral cartridge, included in Little Luxury's six-stage systems, restores them before the water reaches the tap.
What is the difference between an under sink system and a whole house filter?
An under sink system treats water at one tap, usually the kitchen, for high purification. A whole house filter treats water as it enters the property, covering every tap, though not to the same purification level.
