Choosing the right system
Choosing whole-house water filtration
Whole-house (point-of-entry) filtration treats water where it enters your home, so every tap and shower benefits, not just the kitchen. The trick is that "filter" isn’t one thing: the right setup depends entirely on what’s actually in your water. Grewa doesn’t sell filtration yet, so this guide helps you work it out and find a good system now.
Start by knowing your water
Everything follows from what’s in the water. Town water is usually chlorine taste and a little sediment. Tank water can carry sediment, organics and sometimes bugs. Bore water often adds iron, hardness and minerals. A cheap water test kit, or a lab test, tells you what you’re actually dealing with, guessing wastes money on the wrong filter.
Match the filter to the problem
- Sediment and grit: a sediment (spun or pleated) filter, rated in microns.
- Chlorine taste and smell: activated carbon.
- Iron staining: an iron-removal filter.
- Hardness and scale: a softener or scale reducer.
- Bugs in drinking water: UV, but only after the water is filtered clear.
Size it to your flow
A whole-house filter has to keep up with several outlets at once without choking your pressure. Check the system’s flow rate (litres per minute) against your household, an undersized filter drops your pressure. This is also where a pressure pump and filtration have to work together rather than fight.
How to find the right one today
Test your water, then search along the lines of "whole house water filter system Australia" for your source, or use this prompt with your test results:
I want whole-house water filtration in Australia. My water source is [town / rainwater tank / bore]. A water test showed [list what it found, e.g. chlorine, sediment, iron X ppm, hardness Y]. My household is [N] people with [N] bathrooms. What filtration stages should I use, in what order, and what flow rate should the system be rated for so it doesn’t drop my water pressure?
Where Grewa fits
A filtration range is on our roadmap, designed to work with the pressure side and the app. Until then, the guidance above will get you a setup that suits your water, and if you’re running a pressure pump we can help make sure the two don’t fight each other.
Common questions
Does it matter which way the housings are plumbed?
Yes. Every filter housing has IN and OUT marked on the head, and the whole bank must follow the direction of flow. Plumbed backwards a filter clogs quickly and filters poorly, so if a brand-new setup has low flow from day one, this is the first thing to check.
Do I need whole-house, or just an under-sink filter?
Depends on the goal. If you only want better drinking water, an under-sink filter at the kitchen is cheaper and enough. Whole-house makes sense when the issue affects showers, appliances and every tap: chlorine, sediment, iron or hardness across the home.
How do I know what’s in my water?
Test it. A home test kit gives you the basics (hardness, chlorine, iron, pH); a lab test is more thorough. It’s the single best money you can spend before buying any filter.