How to Choose the Right Water Filtration System for Your Home or Property
Better-tasting drinking water, cleaner rainwater, reliable whole-house filtration or protection for your irrigation system. Whatever your goal, choosing the right water filter starts with understanding what you want to achieve.
Water filtration is not one-size-fits-all. A simple underbench filter may be ideal for improving drinking water from a town supply, while a home using rainwater or bore water may benefit from several treatment stages working together.
At WTS, we supply water filtration systems, replacement filter cartridges, UV treatment equipment and specialist filtration solutions for homes, lifestyle properties, farms and irrigation systems throughout New Zealand.
This guide will help you compare the options, understand their benefits and choose a practical solution for your water supply.
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1. Start With What You Want to Improve
The easiest way to choose a water filter is to identify the result you want.
You may have more than one goal, and several filtration methods may achieve similar results. For example, carbon filtration, KDF/GAC and reverse osmosis can all contribute to better-tasting drinking water, but they work differently.
Which water filtration option suits your needs?
| Your goal | Filtration options to consider | Main benefits |
|---|---|---|
| Better-tasting drinking water | Carbon, KDF/GAC, reverse osmosis | Improve taste and odour; reduce selected substances |
| Reduce chlorine taste and smell | Activated carbon, KDF/GAC | Improve the taste of treated town water |
| Remove dirt, rust or sediment | Polyspun, pleated or other sediment filters | Capture suspended particles and help protect equipment |
| Reduce specific dissolved contaminants | Suitable specialist media, KDF/GAC or reverse osmosis | Target particular water quality concerns |
| More comprehensive drinking-water treatment | Multi-stage filtration or reverse osmosis | Combine treatment methods to address several concerns |
| Treat rainwater or bore water for household use | Sediment filtration, appropriate specialist treatment and UV | Improve water quality and provide microbial treatment |
| Filter water throughout the home | Whole-house filter housings or combined treatment systems | Treat water before it reaches household outlets |
| Keep debris out of a rainwater tank | Pre-tank filtration | Remove leaves and larger debris before storage |
| Protect irrigation equipment | Screen, disc or other irrigation filters | Reduce blockages in emitters, valves and sprinklers |
The key is to choose the treatment method for the problem, rather than choosing a filter based on its name or number of stages.
2. Understand the Main Types of Water Filtration
Carbon filtration: better-tasting water for everyday use
Activated carbon is one of the most popular options for improving household drinking water.
It is particularly useful for reducing chlorine taste and odour in treated town water. Depending on the cartridge and its performance specifications, carbon filtration may also reduce certain organic compounds and other unwanted substances.
Carbon filters are available in different forms, including carbon block and granular activated carbon (GAC).
Best suited to:
-Improving drinking-water taste and smell
-Underbench kitchen filtration
-Selected whole-house filtration applications
-Combining with sediment filters or other treatment stages
For many homes on town water, a quality carbon filter is a practical place to start.
KDF/GAC filtration: combined media for targeted treatment
KDF/GAC cartridges combine two treatment media in one filter.
GAC provides adsorption of substances such as chlorine and certain organic compounds, while KDF uses an oxidation-reduction process to address selected contaminants.
This combination can be useful where customers want more than basic taste and odour improvement.
Best suited to:
-Drinking-water filtration
-Selected chlorine and metal reduction applications
-Underbench or whole-house systems using compatible cartridges
-Multi-stage filtration arrangements
The actual substances reduced depend on the cartridge's specifications, water chemistry and operating conditions.
Explore Filter Media and Cartridges
Sediment filtration: remove particles and protect your system
Sediment filtration captures suspended material such as dirt, rust, sand and other particles.
It is commonly used as the first stage in a filtration system, helping protect downstream cartridges, UV equipment, taps and appliances.
Two common cartridge styles are:
-Polyspun filters: Depth filtration that captures particles through the filter material.
-Pleated filters: Larger surface area designs, with some cartridges suitable for cleaning and reuse according to manufacturer instructions.
Sediment filters are available in different micron ratings and sizes.
A finer micron rating captures smaller particles but may require more frequent maintenance or create additional pressure loss.
Best suited to:
-Rainwater and bore water supplies
-Water containing visible sediment
-Pre-filtration before UV treatment
-Protecting downstream filtration equipment
-Whole-house water treatment
Browse Sediment and Replacement Filter Media
Reverse osmosis: more extensive drinking-water treatment
Reverse osmosis (RO) uses a semi-permeable membrane to reduce a broad range of dissolved substances.
Unlike conventional sediment and carbon filters, reverse osmosis can reduce many dissolved salts and other contaminants, depending on membrane performance and system design.
RO systems commonly combine sediment pre-filtration, carbon filtration, a reverse osmosis membrane and sometimes a final polishing stage.
Best suited to:
-Dedicated drinking-water treatment
-Water with particular dissolved contaminant concerns
-Households seeking a more comprehensive point-of-use filtration system
Reverse osmosis is generally installed at a dedicated drinking-water outlet rather than across an entire home. It also produces reject water during operation.
A water test can help determine whether RO is necessary or whether a simpler treatment system will meet your needs.
UV water treatment: protection against microorganisms
Ultraviolet (UV) treatment uses UV light to inactivate susceptible microorganisms, including bacteria, viruses and protozoa, when the system is correctly specified and operated.
It is particularly valuable for homes using private water supplies such as rainwater, bore water or spring water.
UV does not physically remove sediment or dissolved chemicals. For this reason, it is commonly installed after suitable pre-filtration.
A typical household treatment arrangement may include:
Sediment filtration → additional treatment if required → UV disinfection → household supply
Best suited to:
-Rainwater and bore water supplies
-Whole-house drinking-water treatment
-Homes requiring microbial treatment
-Systems combining sediment, carbon and UV stages
WTS supplies standalone UV equipment and combined whole-house systems, including Greenway, Trevoli, Aquashield and other options.
For drinking-water applications, we recommend sizing UV systems using the manufacturer's specified flow rate at a UV dose of 40 mJ/cm², rather than relying on the maximum advertised flow rate.
Explore UV and Whole-House Filtration Systems
3. Underbench or Whole-House Filtration: Which Is Better?
The right installation depends on whether you want to treat water at one outlet or throughout the property.
| Feature | Underbench filtration | Whole-house filtration |
|---|---|---|
| Main purpose | Drinking and cooking water | Water supplied to multiple household outlets |
| Installation | Beneath the kitchen bench | On the main water supply line |
| Typical options | Carbon, KDF/GAC, multi-stage, RO | Sediment, carbon, specialist media, UV |
| Main benefit | Targeted treatment where you use drinking water | Treatment across the household |
| Suitable for | Town water and appropriately treated private supplies | Town, rainwater and bore supplies |
| Maintenance | Cartridge or membrane replacement | Cartridge servicing and, where fitted, UV maintenance |
Choose underbench filtration when:
You mainly want to improve the taste or quality of water used for drinking and cooking.
An underbench system can provide an effective, discreet solution without treating water used for showers, laundry or outdoor taps.
Options range from compact carbon filtration kits to multi-stage systems and reverse osmosis.
For a more detailed look at underbench filtration, read our guide to choosing an underbench water filter.
Choose whole-house filtration when:
You want treatment across multiple outlets or need to manage the quality of water entering your home.
Whole-house systems are particularly useful for properties supplied by rainwater tanks or bores, where sediment filtration and UV treatment may be important parts of the overall system.
A combined system can also make installation and maintenance more straightforward by bringing several treatment stages together.
Read our guide to Whole-House Filtration HERE
4. Choosing Filtration for Rainwater and Bore Water
Private water supplies often require a different approach from treated town water.
Rainwater can collect debris and contaminants from roofs and gutters, while bore water quality varies according to local geology and surrounding conditions.
The best solution may involve several treatment stages.
Rainwater filtration
For homes collecting roof water, consider filtration at two points.
Before the tank: A pre-tank filter helps intercept leaves and other debris before they enter storage.
After the tank: Sediment filtration, additional treatment where needed, and appropriately sized UV disinfection can prepare water for household use.
WTS supplies pre-tank filtration options including Maelstrom and Aqua Filter products, alongside whole-house treatment equipment.
Read more about Pre-Filtration HERE
Bore water filtration
Bore water can contain naturally occurring minerals and dissolved substances that require specialised treatment.
Depending on the water test results, treatment may include sediment filtration, iron or manganese removal, pH correction, other specialist media and UV disinfection.
Because bore water quality varies considerably, a tailored solution is often more effective than choosing a standard cartridge without understanding the water chemistry.
For private drinking-water supplies, water testing is the best starting point for determining what treatment is required.
5. Don't Forget Irrigation and Pre-Tank Filtration
Not all filtration is designed for drinking water.
Irrigation filtration
Irrigation filters protect equipment by capturing particles before they reach sprinklers, valves, drippers and emitters.
Screen and disc filters are common options, with the appropriate mesh size selected to suit the equipment and water source.
Good filtration helps reduce blockages, maintain more consistent water distribution and minimise unnecessary servicing.
WTS supplies irrigation filtration equipment, including Rain Bird options, for domestic, landscape and agricultural applications.
Pre-tank filtration
Removing debris before rainwater enters a storage tank can reduce the accumulation of organic material and sediment.
Pre-tank filters are a useful part of a rainwater harvesting system, particularly where roofs are exposed to leaves and other environmental debris.
They complement, rather than replace, any treatment required to make stored water suitable for drinking.
Read more about Pre-Filtration HERE
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6. Choosing the Right Filter Size and Cartridge
Once you have identified the filtration type, the next step is selecting equipment that suits your installation.
Consider:
Flow rate: The filter needs to accommodate the water demand without excessive pressure loss.
Micron rating: Select a particle rating suited to the water quality and the equipment being protected.
Cartridge size: Check whether your housing requires a standard 10-inch, jumbo 10-inch, jumbo 20-inch or another cartridge size.
Water pressure: Confirm the housing and treatment equipment are rated for the operating pressure.
Water chemistry: Select specialist media based on the contaminants you need to reduce.
Servicing requirements: Consider cartridge life, replacement availability and ongoing maintenance.
A well-selected system balances water quality, flow, pressure and maintenance.
For replacement cartridges, always confirm the correct size and compatibility with your existing filter housing.
7. Shop the WTS Water Filtration Range
Whether you are improving drinking water, replacing an existing cartridge or planning a complete treatment system, WTS has a range of options to help.
| What you're looking for | Where to shop |
|---|---|
| Complete filtration systems, including multi-stage and UV options | Filter Systems |
| Carbon, sediment, KDF/GAC and replacement cartridges | Filter Media |
| Whole-house equipment, UV, pre-tank and irrigation filtration, plus the wider product range | All Filtration Products |
Find the Right Water Filtration Solution With WTS
The best water filter is one that suits your water supply, delivers the results you want and works reliably with your existing plumbing or water system.
For some households, that means a straightforward underbench carbon filter. For others, it may be a multi-stage whole-house system, UV disinfection or specialist treatment based on water test results.
WTS can help with product selection, system design, installation and servicing, whether you are upgrading an existing filter or planning a new water treatment system.
Ready to improve your water?