W4 reverse osmosis membrane

The reverse osmosis membrane is the main fine-filtration element. The stated water ratio is two parts filtered water to one part reject water. Filtration targets include:

• E. coli bacteria
• Heavy metals
• Radiological contaminants — check the system’s specific performance
• Agricultural chemicals
• Pharmaceutical residues and hormones
• Microplastics
• PFAS, also known as forever chemicals
• Benzene
• Chlorine
• Fluoride
• Iron
• Limescale
• Unpleasant odours

The indicator shows the membrane’s remaining life: yellow means it is running low; red means replacement is due.