Rainwater filter

Doulton Twin Rainwater Alkaliser Undersink

m-doulton best-price-guarentee

Neat and compact, the Royal Doulton Superblock Twin Undersink water filtration system can be conveniently installed under the sink and comes with your choice of attractive, designer chrome taps, at no extra charge. The taps can be easily mounted on your stainless steel sink, or corona or granite bench-top.

The additional stages of this system have been designed particularly to cater to the possible acidic levels of collected rain water.

The additional 3rd stage of filtration, namely the Kalcor Alkaliser Filter is used as a pre-alkalising filter; using naturally occurring minerals to raise the pH from sub-neutral to neutral or slightly alkaline pH levels.

This stage is then followed by the Alkahydrate alkaliser filter that effectively raises pH levels as well as producing antioxidant and oxygenating qualities. The final result is pure, great tasting water with the health and life enhancing qualities of a high alkaline pH level.


Effectively Removes

  • 99.99% Parasites & Cysts
  • 99.99% Cryptosporidium & Giardia
  • 99.99% Bacteria
  • 99.99% Sediment, Dirt, Rust
  • 99.99% Salmonella
  • 99.3% Cholera
  • 99.99% e.Coli Bacteria
  • 99.00% Residual Chlorine Content
  • 99.3% Bromodichloromethane
  • 99.3% Bromoform
  • 99.5% Chloroform
  • 99.3% Dibromochloromethane
  • 99.7% Zinc
  • 99.9% Iron
  • 99.9% Lead
  • 99.9% Manganese
  • 99.9% Cadium
  • 99.9% Copper
  • 99.9% Mercury
  • 96.7% Aluminium

Filtration Process

4-Stage filtration process

Stage 1 – Doulton Ceramic 0.9 micron absolute Pre-filter Made in UK

The first stage filter cartridge in the Twin Rainwater Alkaliser Undersink System has two important functions:

  1. Mechanically filters out harmful bacteria and parasites as well as dirt, rust and sediment.
  2. Removing the above contaminants protects the Carbon Block cartridge allowing it to function more effectively and last longer.
Stage 2 – Carbon Block 1 micron Post-filter

The Doulton Twin Undersink combines Ultra-fine ceramic technology with a premium one micron carbon block filter manufactured in USA. The one micron carbon block filter effectively removes all chlorine, chemicals, pesticides, unpleasant tastes and odour along with harmful heavy metals. Made from premium coconut-shell carbon, fresher, sweeter tasting water is ensured.

With the Royal Doulton Superblock Twin Undersink Filter your family will be guaranteed micro-biologically safe drinking water.

Stage 3 – Proprietary Kalcor Alkaliser Filter

Stabilising the water pH level.

Stage 4 – Alkahydrate Alkaliser filter

The Alkahydrate alkaliser filter effectively raises pH levels as well as producing antioxidant and oxygenating qualities. The filter also emits far-infrared rays which result in shorter cluster chains in the water molecules – increasing the bio-available response and oxygen absorption in the body.

Of all the accessories we supply, our latest addition is the pH Testing Kit. To complement our new range of Alkaliser Filter Systems, easy step by step use of this kit can identify the precise pH level of your drinking water supply. You may be surprised with the results!

Features & Benefits

The Doulton Twin Undersink is self maintainable. If the flow rate slows, the Doulton Sterasyl ceramic cartridge can be cleaned easily with a quality scrubing pad such as Scotch Brite™ under running water. Cleaning frequency will vary depending upon water quality.

The Royal Doulton Ultracarb Ceramic Cartridge has been tested and certified by the Hong Kong Standards and Testing Centre (No: HC109730) and the National Sanitation Foundation (NSF53).


Filter output 5,000 litres* per day
Max flow rate 3 litres per minute
Micron rating 0.9 micron absolute

*It is recommended that the cartridge be changed every 6-12 months according to the water quality and usage.