The 70L membrane is a critical component in Rainman watermakers, responsible for extracting potable fresh water from filtered, pressurised seawater. Using high-performance Filmtec SW30 reverse osmosis technology, this membrane supports reliable desalination with output suited to systems producing up to 70 litres per hour.

With proper care, the membrane can last 5 to 10 years. Over time, total dissolved solids (TDS) levels may increase, and most users choose to replace the membrane when readings reach 700–800 ppm. While long-lasting, membranes are sensitive to biological fouling and should be flushed regularly to prevent damage.

Rainman systems use standard-size membranes, making global replacement simple. This model is available in SW30-2540 (2.5” x 40”) or SW30-2521 (2.5” x 21”), depending on the system configuration.

• Key desalination component for Rainman watermakers
• Filmtec SW30 membrane for high salt rejection and flow rate
• Suitable for 70L/hour systems
• Long service life with proper flushing and care
• TDS levels indicate when replacement is needed
• Available in standard SW30-2540 or SW30-2521 sizes
• Easy to source globally