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How Will A Rainwater Pre-Tank Filtration System Help You?

RainWatch provides the Australian engineered Rainwater Tank Filtration System. It’s the easiest, lowest maintenance way to ensure the cleanest rainwater tank possible!

Our Rainwater Tank Filtration Systems will intercept contaminated rainwater that is picked up from your roof. These contaminants may be bird dropping, dirt and insects. The patented RainWatch filter mesh removes 99.9% of airborne contaminants, leaving only the rainwater to make its way to the tank. This ensures you collect clean rainwater with no additional impurities.

The RainWatch Filter is a pre tank filtration system, which means easy installation, cleaning and replacing the cartridge filter! See the Pre Tank Rainwater Filter Installation process.

View our RainWatch Rainwater Tank Filter Pack and Rainwater Tank Filter Cartridge.

Removes 99.9% of All Airborne Contaminants* & Removes 92% Bacteria*

People worldwide are becoming increasingly concerned with municipal mains water supplies, and in New Zealand, in August 2016 some 45 people were hospitalised which resulted in 3 deaths due to contaminated water coming from underground water supplies.

It is therefore important to know where the water you drink comes from and in Australia municipal mains water is monitored for 70 different contaminants, including cryptosporidium, bacteria and some pesticides.


There is evidence to suggest that when people are exposed to more than one pesticide, the blood concentrations of the individual pesticides are up to 100 times greater than during exposure to a single toxin. Furthermore, lead in Australian plumbing fittings was legal until 1989 while chlorine is commonly used to disinfect water from deadly diseases including dysentery, typhoid and cholera and has been linked to various health problems.

The RainWatch Water Tank Filtration System makes sense in ensuring that rainwater from the heavens remains pure as nature intended it to be and when combined with a complete filtration system, rainwater has the potential to be a safe and viable source of drinking water all year round.

Download independent Test Results for Airborne Contaminants

Download independent Test Results for Bacteria

Suitable for all rainwater tanks

There’s a lot of variety when it comes to rainwater tanks. The smallest holds 30L of rainwater, while some of the largest have the capacity to hold 378,000L. Our Rainwatch Filter is designed to work in conjunction with any make of rainwater tank.

The RainWatch Filter doesn’t require an additional gradient toward the tank (ie, a downward slope) and can be fitted to an existing horizontal stormwater line (cannot be fitted vertically) and with an annual rainfall of 300mm can accommodate a roof area up to 100m2 per filter.

Our recommendation is to fit one RainWatch Filter for every gutter outlet based on your areas annual rainfall:

300mm = One RainWatch Filter per 50 -100m2 of Roof

400mm = One RainWatch Filter per 50m2 of Roof

400mm and above = One RainWatch Filter per 25m2 of Roof

Note:  A RainWatch Filter fitted (with an overflow) to larger areas than recommended will still deliver high volumes of high-quality rainwater; however, the RainWatch Filter will require more regular cleaning.

Filters Particles down to 50 microns in size


Traditional rainwater systems have the potential to pump contaminated or dirty water through your filters to your point of use. When this water passes through a pump, the pollutants are broken down into smaller particles making them difficult to fully remove. The addition of a pre-tank filter eliminates this flaw and delivers a new quality of rainwater.

The easy-clean 50-micron stainless steel membrane in the RainWatch Filter extracts particles before they are able to become tank sediment, which not only increases the quality of the rainwater, but also reduces the hassle of cleaning your tank. The RainWatch Filter is designed to work as a complementary system to all current rainwater catchment systems.

Won’t wastewater


Unlike other pre tank rainwater filters that use runoff or a cleaning chamber for larger contaminants, our RainWatch system uses a drip-feed discharge device. This allows the RainWatch Filter to discharge stored soiled rainwater, meaning no runoff of spill is required.

Easy and Quick to Clean


The patented RainWatch Filters 316 50-micron stainless steel screen makes it easy to clean dirty contaminants from the filters membrane while the 50-micron screen produces crystal clean rainwater, even after several months of exposure to heavily soiled rainwater.

The RainWatch Filters high volume low-pressure flow cycle will consistently deliver high-quality rainwater. The RainWatch Filter is easy and quick to clean. The RainWatch Filters canister easily unclips by hand allowing accessible cleaning of the entire filter while the stainless steel filter pad can BE HOSED DOWN in cold water which means no more costly filter cartridge replacements every time you clean your RainWatch Filter.


Removes Insects and Stops Mice and Rats


Don’t let your rainwater tank become detritus soup.

Without a pre-tank filter, dead insects and bird droppings will eventually find their way into your rainwater tank where that will further decay, compromising the quality of your stored water.

The RainWatch Rainwater Tank Filtration System prevents the storage of incoming matter down to half the size of a human hair, far smaller than any insect is capable of dis-assembling to.