Reverse Osmosis Water Filter
Reverse osmosis (RO) water filter systems use a semipermeable membrane — along with pre- and post-filter stages — to remove a broad range of dissolved solids, particulates, and impurities from your water. Awesome Water Filters stocks a range of RO systems for under-sink installation, along with genuine replacement membrane and stage cartridges to keep your system performing at its best.
Browse the full range below.
How Does Reverse Osmosis Work?
Reverse osmosis pushes water under pressure through a semipermeable membrane. The membrane's fine pores allow water molecules to pass through while rejecting many dissolved solids — including salts, minerals, and other substances — which are flushed away in a concentrate stream (commonly called reject or brine water). Most RO systems include additional pre-filter stages (typically sediment and carbon) to protect the membrane from fouling, and a post-filter to polish the taste of the treated water before it reaches your tap.
RO systems require a connection to your mains water supply and produce some waste water as part of the process. The ratio of treated water to waste water varies by system and incoming water pressure.
Is Reverse Osmosis Right for Your Household?
Reverse osmosis is one of the more comprehensive domestic water treatment options available. It suits households that:
- Want multi-stage filtration of their drinking water
- Are on bore water or tank water with high dissolved solids (with appropriate pre-treatment)
- Have specific water quality concerns they've identified through water testing
- Use significant volumes of filtered water daily
RO systems are typically plumbed under the kitchen sink with a dedicated tap. Installation involves connection to the mains water supply — in most Australian states, this work must be carried out by a licensed plumber. Check the requirements in your state or territory before proceeding.
RO System Maintenance: Cartridge Replacement
To maintain performance, RO systems require regular replacement of their filter stages. As a general guide:
- Pre-filter cartridges (sediment, carbon): Every 6–12 months
- RO membrane: Every 2–3 years under normal municipal water conditions
- Post-filter cartridge: Every 12 months
Water quality, usage volume, and incoming sediment levels will affect these intervals. If you notice reduced flow rate or a change in taste, inspect your cartridges sooner. We stock replacement RO cartridges and membranes for the systems we sell.
Frequently Asked Questions
Does reverse osmosis remove fluoride?
RO membranes can reduce fluoride levels — the actual reduction achieved depends on the specific membrane, your water pressure, temperature, and incoming fluoride concentration. Check the product documentation and any available test data for the specific system you're considering. We recommend verifying performance claims against documented test results before purchasing if fluoride reduction is a priority.
How much water does an RO system waste?
This varies by system design and your inlet water pressure. Higher-efficiency systems waste less water per litre of treated output. Check the product specifications for the waste ratio. Some waste water can be repurposed for garden watering or cleaning if it doesn't contain concerning levels of the substances being removed.
Do I need a plumber to install an RO system?
RO systems require connection to your cold water supply and drainage for the reject water. In most Australian states and territories, work on mains-connected plumbing must be performed by a licensed plumber. Confirm the requirements in your state before attempting self-installation.
Can I use RO-treated water for everything?
Most households use their RO system for drinking water and cooking from a dedicated tap. RO treatment of all household water is generally not practical or necessary for most residential applications — for whole-property treatment, see our Whole House Water Filters.