A 7-stage Reverse Osmosis (RO) system builds on the standard 5-stage system by adding extra filters for enhanced water quality, typically including alkaline remineralization and UV sterilization. These additions aim to improve taste, pH balance, and microbiological safety. Stage 1: Sediment Filter (5 Micron or Lower) Function: Removes dirt, sand, rust, and debris. Purpose: Protects and extends the life of the carbon filters and membrane. Stage 2: Granular Activated Carbon (GAC) Filter Function: Removes chlorine, chloramine, VOCs, and chemicals. Purpose: Protects the RO membrane and improves taste/smell. Stage 3: Carbon Block Filter Function: Further refines chemical filtration. Purpose: Ensures maximum chlorine and contaminant removal before the RO membrane. Stage 4: RO Membrane Function: Removes up to 95–99% of dissolved solids, including: Heavy metals (lead, arsenic, chromium) Fluoride Nitrates/nitrites Bacteria and viruses Core stage of purification. Stage 5: Post Carbon Filter (T33 or Polishing Filter) Function: Removes any residual taste/odor after water is stored in the RO tank. Purpose: Final taste enhancement. Stage 6: Alkaline Remineralization Filter Function: Adds beneficial minerals like calcium, magnesium, potassium. Purpose: Improves taste and mouthfeel. Raises pH (alkalizes the water). Counteracts the “flat” taste of pure RO water. Stage 7: UV Sterilization Light Function: Uses ultraviolet light to kill bacteria, viruses, and other microbes. Purpose: Provides biological protection, especially important for: Well water Areas with boil-water advisories Travelers or off-grid homes Related
