Alkaline Filtration: Best Systems for Australian Homes in 2025
Updated: April 2025 | Category: Alkaline Filters | Reading time: 12 min
Alkaline filtration systems raise your drinking water’s pH to a healthy 8.0–9.5 range while removing contaminants like chlorine, heavy metals, and sediments. Whether you want an undersink reverse osmosis setup, a benchtop gravity-fed unit, or a compact 3-stage system, this guide covers the top options available to Australian buyers — with real specs, honest pros and cons, and direct links to buy.
- Top 5 Alkaline Filtration Systems at a Glance
- Spec Comparison Table
- 1. Shield Triple Undersink Alkaline System
- 2. 3-Stage Undersink Alkaline Filter (Silver Alkaline)
- 3. 5-Stage Alkaline Reverse Osmosis 150G
- 4. Aimex 16L Bench Top 8-Stage Purifier
- 5. Phoenix Gravity 12L Stainless Steel Filter
- Head-to-Head Comparison
- FAQ
- Final Verdict
Top 5 Alkaline Filtration Systems at a Glance
Shield Triple Undersink Alkaline Filter System
WaterMark Certified • 3-Stage • Undersink
3-Stage Silver Alkaline Undersink Filter
Silver Alkaline Tech • SUS304 Tap • Compact
5-Stage Alkaline Reverse Osmosis 150G RO System
Reverse Osmosis • 150GPD • 8L Tank
Aimex 16L Bench Top 8-Stage Alkaline Purifier
Benchtop • 8-Stage • SGS Certified
Phoenix Gravity 12L Stainless Steel Filter
NSF Certified • Gravity-Fed • No Electricity
Spec Comparison Table
| Feature | Shield Triple | 3-Stage Silver Alkaline | 5-Stage RO 150G | Aimex 16L Benchtop | Phoenix Gravity 12L |
|---|---|---|---|---|---|
| Type | Undersink | Undersink | Undersink RO | Benchtop | Countertop Gravity |
| Filtration Stages | 3 | 3 | 5 | 8 | 2 (carbon) |
| Alkaline Method | Alkaline cartridge | Silver alkaline filter | RO + alkaline remineralisation | KDF + alkaline media | Carbon filtration |
| Chlorine Removal | 99% | 99% | 99%+ | Yes | Yes (NSF certified) |
| Capacity/Flow | Standard flow | Standard flow | 150 GPD | 16 litres | 12 litres |
| Tap Included | SUS304 lead-free | SUS304 stainless | Stainless steel | Built-in spigot | Built-in spigot |
| Certification | WaterMark AU | WaterMark AU | WaterMark AU | SGS tested | NSF certified |
| Installation | Under sink (plumbing) | Under sink (plumbing) | Under sink (plumbing) | None (benchtop) | None (gravity-fed) |
| Electricity Needed | No | No | Yes (pump) | No | No |
| Best For | Families wanting certified quality | Compact kitchens | Maximum purification | Renters & easy setup | Off-grid & eco-conscious |
1. Shield Triple Undersink Alkaline Water Filter System
Overview
The Shield Triple is an Australian WaterMark-certified undersink system that delivers alkaline water through a dedicated SUS304 stainless steel tap. Its 3-stage filtration removes up to 99% of chlorine, balances pH levels, and filters out heavy metals and sediments. The quick-change cartridge design means you can swap filters in seconds without tools — and the bundle includes an extra 12 months of replacement cartridges for extended value.
Key Specs
- Stages: 3 (sediment, carbon block, alkaline)
- Chlorine Removal: Up to 99%
- Tap: Premium SUS304 lead-free stainless steel
- Certification: WaterMark (Australian plumbing standard)
- Extras: 12-month replacement cartridge set included
Pros
- WaterMark certified for Australian compliance
- Quick-change cartridges — no tools needed
- Premium SUS304 lead-free tap included
- Extra year of replacement filters bundled
- Effective 99% chlorine removal
Cons
- Requires under-sink plumbing installation
- No built-in TDS or pH meter
- Limited to 3-stage filtration (no RO membrane)
2. 3-Stage Undersink Alkaline Filter (Silver Alkaline Technology)
Overview
This compact 3-stage undersink system uses innovative silver alkaline technology that not only raises water pH for a healthy alkaline balance but also provides antibacterial properties. The 0.5μm coconut carbon block delivers superior chlorine and odour removal, while the durable SUS304 stainless steel tap adds a modern, lead-free dispensing point to your kitchen.
Key Specs
- Stages: 3 (sediment, 0.5μm coconut carbon block, silver alkaline)
- Chlorine Removal: Up to 99%
- Carbon Block: 0.5 micron coconut shell activated carbon
- Tap: SUS304 stainless steel, lead-free
- Certification: WaterMark certified
Pros
- Silver alkaline tech adds antibacterial protection
- Ultra-fine 0.5μm carbon block for superior filtration
- Compact design saves under-sink space
- Quick-change filters — zero bacteria exposure
- WaterMark certified
Cons
- Requires plumbing connection
- No storage tank — filters on demand only
- Replacement filters may be harder to source locally
3. 5-Stage Alkaline Reverse Osmosis 150G RO System
Overview
For maximum purification, this 5-stage reverse osmosis system pushes water through a high-flow 150GPD membrane, removing up to 99% of total dissolved solids including fluoride, heavy metals, and microplastics. The final alkaline remineralisation stage adds back calcium and magnesium, lifting pH to a healthy 8–9 range. Comes with a stainless steel tap and 8-litre pressurised storage tank for instant dispensing.
Key Specs
- Stages: 5 (PP sediment, GAC, carbon block, 150G RO membrane, alkaline remineralisation)
- Flow Rate: 150 gallons per day
- Storage: 8-litre pressurised tank
- TDS Removal: Up to 99%
- pH Output: 8.0–9.0 (weak alkaline)
Pros
- Highest purification level — removes fluoride, heavy metals, TDS
- High 150GPD flow rate
- Alkaline remineralisation restores minerals post-RO
- 8L tank for ready-to-drink water
- Stainless steel tap included
Cons
- Produces wastewater (typical of RO systems)
- Requires electricity for the booster pump
- More complex installation than non-RO systems
- Higher ongoing filter replacement costs
4. Aimex 16L Bench Top 8-Stage Alkaline Purifier
Overview
The Aimex 16L is a gravity-fed benchtop unit that requires zero installation — just fill the top chamber and let gravity do the work. Its 8-stage filtration includes ceramic, activated carbon, KDF media, alkaline minerals, and more. The food-grade BPA-free housing holds 16 litres and has been independently tested by SGS for quality assurance. Perfect for renters or anyone who wants alkaline water without modifying plumbing.
Key Specs
- Stages: 8 (ceramic, activated charcoal, KDF, alkaline mineral balls, etc.)
- Capacity: 16 litres
- Material: Food-grade BPA-free plastic
- Certification: SGS third-party tested
- Installation: None — benchtop gravity-fed
Pros
- No plumbing or electricity required
- 8-stage filtration for thorough purification
- Large 16L capacity for families
- SGS certified quality
- Very affordable entry point
Cons
- Gravity-fed = slower than pressurised systems
- Plastic housing (not stainless steel)
- Takes up benchtop space
- Filters need replacement every 6–8 months
5. Phoenix Gravity 12L Stainless Steel Filter
Overview
The Phoenix Gravity is a premium countertop gravity filter built from NSF-certified AISI 304 stainless steel. It includes two Smart Carbon cartridges with long lifespans, needs no electricity or plumbing, and assembles in minutes. Its all-metal construction is durable and eco-friendly, making it ideal for off-grid living, camping, or anyone who wants a chemical-free, sustainable filtration solution.
Key Specs
- Material: AISI 304 stainless steel (NSF certified)
- Capacity: 12 litres
- Filters: 2 Smart Carbon cartridges included
- Power: None — gravity-fed
- Installation: None — countertop, assembled in minutes
Pros
- Premium 304 stainless steel construction
- NSF certified filtration
- No electricity or plumbing needed
- Long-lasting replaceable cartridges
- Eco-friendly and economical
Cons
- Smaller 12L capacity than Aimex
- Only 2-stage carbon filtration
- No dedicated alkaline remineralisation stage
- Higher upfront cost for stainless build
Head-to-Head Comparison
| Criteria | Best Pick | Why |
|---|---|---|
| Best Overall | Shield Triple Undersink | WaterMark certified, quick-change filters, extra cartridges bundled |
| Best Purification | 5-Stage Alkaline RO 150G | RO membrane removes 99% TDS including fluoride and heavy metals |
| Best Compact | 3-Stage Silver Alkaline | Space-saving undersink design with antibacterial silver technology |
| Best No-Install | Aimex 16L Benchtop | 8-stage filtration, no plumbing, ideal for renters |
| Best Build Quality | Phoenix Gravity 12L | NSF-certified 304 stainless steel, eco-friendly, no power needed |
| Best for Families | Aimex 16L Benchtop | Large 16L capacity handles household demand easily |
| Best for Off-Grid | Phoenix Gravity 12L | Zero electricity, gravity-fed, portable stainless construction |
Frequently Asked Questions
- What is alkaline filtration and how does it work?
- Alkaline filtration raises the pH of your drinking water to between 8.0 and 9.5 using mineral media such as calcium, magnesium, and alkaline ceramic balls. Some systems achieve this through remineralisation after reverse osmosis, while others use inline alkaline cartridges or mineral stones in gravity-fed units.
- Is alkaline water actually healthier than regular tap water?
- Research suggests alkaline water may help neutralise acid in the body and improve hydration. While the health claims are still debated, many Australians prefer the smoother taste and mineral content that alkaline filtration provides. The real benefit often comes from the contaminant removal that happens alongside the pH adjustment.
- Do I need a plumber to install an undersink alkaline filter?
- Most undersink systems like the Shield Triple and 3-Stage Silver Alkaline can be DIY-installed with basic tools and the included fittings. However, if you are not confident with plumbing connections, hiring a licensed plumber is recommended to ensure WaterMark compliance and avoid leaks.
- How often do alkaline filter cartridges need replacing?
- Replacement intervals vary by system: undersink carbon and alkaline cartridges typically last 6–12 months, RO membranes last 2–3 years, and benchtop gravity filters need new cartridges every 6–8 months depending on usage and source water quality.
- Can I use an alkaline filter with tank (rainwater) water?
- Yes, but for rainwater you should choose a system with a ceramic or sediment pre-filter to handle particulates. Gravity-fed systems like the Aimex and Phoenix are popular choices for rain and tank water in rural Australia.
- What is the difference between alkaline filtration and a water ioniser?
- Alkaline filters use mineral media to passively raise pH, while ionisers use electrolysis (electricity) to split water into alkaline and acidic streams. Filters are simpler, cheaper, and require no power. Ionisers offer adjustable pH but cost significantly more upfront.
- Are these systems suitable for Australian water conditions?
- Absolutely. All five systems reviewed here are sold in Australia and designed for local water conditions. The WaterMark-certified units (Shield Triple, 3-Stage Silver, and 5-Stage RO) comply with Australian plumbing standards, while the Aimex and Phoenix are certified by SGS and NSF respectively.
Final Verdict
| Your Situation | Our Recommendation |
|---|---|
| Want certified quality with easy maintenance | Shield Triple Undersink — WaterMark certified with bundled spare cartridges |
| Need maximum contaminant removal (fluoride, heavy metals) | 5-Stage Alkaline RO 150G — RO membrane removes 99% of TDS |
| Small kitchen, want compact undersink | 3-Stage Silver Alkaline — antibacterial tech in a space-saving design |
| Renting or want zero installation | Aimex 16L Benchtop — 8-stage gravity filter, just place and pour |
| Off-grid, eco-conscious, or want premium build | Phoenix Gravity 12L — NSF-certified stainless steel, no power needed |
No matter which system you choose, switching to alkaline filtration means cleaner, better-tasting water with a healthier mineral balance. All five of these systems are excellent choices for Australian households — your best pick comes down to installation preference, budget, and how thorough you want the filtration to be.

