4 Steps to Treat a High-Iron Pool

Add a metal sequestrant first Do not add chlorine or adjust pH until you have treated the iron. Use a pool-specific sequestrant labeled “metal control” or “stain preventer” and run the filter for 24 hours.

Then test your water The sequestrant will not significantly affect pH, alkalinity, or chlorine readings. Testing after treatment gives you accurate baseline numbers.

Balance alkalinity, then pH, then chlorine Adjust alkalinity to 80-120 ppm, pH to 7.4-7.6, and chlorine to 1-3 ppm in that order. This sequence prevents chemical conflicts.

Never shock without sequestrant Shocking a high-iron pool without sequestrant turns the water brown, green, or cloudy and causes stubborn stains. Buy a good sequestrant before any shock.