


“Diamond” purity in your water with double membrane technology and surgical-grade stainless steel.
Technical specifications
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2+8 Year Warranty
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Rainwater Black Diamond goes beyond standard water purifiers as a double membrane water purification system. Developed for under-counter use, this system delivers an impressive purification capacity of 240 litres per day despite its compact size. With a smart LED tap that suits the look of modern kitchens and superior material quality, it brings health and technology together.
Thanks to the double membrane design, the water passes through two membranes; harmful substances, heavy metals and microorganisms are removed while good minerals are retained.
Purified water is stored in a corrosion-resistant grade 304 stainless steel tank and does not come into contact with a plastic tank.
Its specially designed modern tap lets you monitor filter status with intuitive colour codes. Thanks to the LED lights, you can easily keep track of when the filter needs replacing and drink every glass with confidence.
Black Diamond removes contaminants from the water while retaining beneficial minerals such as calcium, magnesium and potassium. It produces soft, great-tasting alkaline water that supports the body's pH balance.

By bringing together hygiene, health and technology in water purification systems, Rainwater offers consumers the longest-lasting, highest-quality and most economical devices

Mounted under the counter in your kitchen, Black Diamond takes up 50% less space than its competitors, helping you save space.

A red light shows it is time to replace the filter; a blue light shows the water is safe to drink.

The purified water is held in a corrosion-resistant stainless steel tank.

The Black Diamond water purifier effectively filters out sediment, chlorine, heavy metals and other harmful substances in your water. This ensures that the water you drink is clean and safe and reduces your risk of waterborne illnesses.









Through the connection, mains water first enters the pre-filter, which has 5-micron pores. The job of this high-tech filter is to remove coarse impurities in the water, that is, sediment such as dust, sand, algae and insects, down to 5 microns. Even after the sediment filter has captured suspended particles and bacteria larger than 5 microns and the water has become much clearer, it may still contain some microorganisms, dissolved chemicals and minerals.
The water then reaches the carbon block filter. The job of the carbon block filter is to remove organic matter that causes unpleasant taste, odour and colour, as well as chlorine and any gaseous odours in the water. It makes the water tastier, clearer and odourless. It filters the water, which the sediment filter has filtered down to 5 microns, to a precision of 1 micron, providing advanced filtration.
Hyperfiltration, the heart of the system, has a semi-permeable membrane structure. It operates at a pressure of at least 2.5 atmospheres. Its pores measure between 8 and 10 angstroms. Heavy metals such as lead, mercury, nitrate, arsenic and copper that may be dissolved in the water, as well as other chemicals or contaminants such as bacteria and limescale, have no chance of passing through this semi-permeable membrane, whose pores are about a millionth of a millimetre. Only water molecules and anions and cations beneficial to human health pass through this filter.
Finally, on its way from the tank to the tap, the water reaches the alkaline filter, whose performance is doubled by the use of ceramic and coconut shell, to gain flavour. This filter's job is to remove odour-causing substances, prevent the formation of microorganisms and balance the pH of the drinking water between 8.5 and 9.0. Enriched with silver ions to improve its taste and with its alkaline pH raised, the water becomes rich in calcium, magnesium, sodium, potassium, iron, phosphorus and other minerals that nourish our bodies.
The confidence of flawless quality: freshness and peace of mind for everyday life.
CE certificate
FDA certificate
Water Quality
TÜV Cert ISO 14001
NSF certificate
TÜV Cert ISO 9001
Düzen Norwest
Hacettepe University
Istanbul Technical UniversityOur systems use PARKER – LIQUIFIT – LEGRIS brand components and comply with the US Food and Drug Administration (FDA) regulations, CFR 21.
Black Diamond is a double membrane water purifier that fits under the counter and purifies water by passing it through two membranes; in the final stage, its alkaline mineral filter gives the water a mineralised taste with a pH of 8+.
For those who want purified, alkaline drinking water at home or in the office. It has a daily purification capacity of 240 litres; measuring 47 × 42 × 17 cm, it takes up little space under the counter.
The unit is installed under the counter and connected to the mains water supply. The water passes through four stages: the sediment filter removes rust, sediment and large particles; the pre-carbon filter removes chlorine, unpleasant odours and organic matter; the double membrane removes harmful substances and heavy metals; and the alkaline mineral filter improves the taste of the water, retains beneficial minerals such as calcium, potassium, sodium and magnesium, and raises the pH above 8. The purified water is held in a 304 stainless steel tank and drawn from the tap on the counter.
Black Diamond is mounted under the counter and connected to the mains water supply. The product is covered by a 2+8 year warranty. For filter replacement and maintenance, you can submit a request via the technical service form.
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It has a double membrane design that passes the water through two membranes; in the final stage, the alkaline mineral filter adds minerals to the water and raises its pH to 8+.
Its daily purification capacity is 240 litres; you can choose an 8 L or 12 L tank.
The LED light on the tap shows the filter status with a colour code and alerts you when it is time for replacement.
It is covered by a 2+8 year warranty.