The table below summarises key water chemistry parameters used in treatment design. Values are indicative; target limits depend on the application and final use.
| Parameter | Common unit | Typical raw water range | Notes |
|---|---|---|---|
| pH | pH units | 6.5 – 8.5 | Acidic water damages metals; high pH causes scaling |
| Total dissolved solids (TDS) | mg/L | 50 – 2,000+ | RO removes most dissolved solids |
| Total hardness | mg/L as CaCO₃ | 50 – 500 | Softening or antiscalant needed for RO |
| Iron (Fe) | mg/L | 0.1 – 10 | Causes staining; removed by oxidation/filtration |
| Manganese (Mn) | mg/L | 0.05 – 2 | Removed with iron or dedicated media |
| Turbidity | NTU | 1 – 200+ | Must be low before RO or UV |
| Chloride | mg/L | 10 – 500 | High levels affect taste and corrosion |
| Nitrate | mg/L as NO₃ | 5 – 100 | RO or ion exchange reduces nitrate |
| Fluoride | mg/L | 0.1 – 10 | Excess fluoride causes dental/skeletal fluorosis |
| Coliform bacteria | CFU/100 mL | Variable | Disinfection required for potable use |
Always send a water sample to a certified laboratory before designing treatment.