Chemistry
Sanitizer cannot keep up
Low free chlorine, high demand, or a stabilizer mismatch can let fine organic material build up.
Troubleshooting guide
Cloudy Pool Water: Find the Cause First
Cloudiness is usually a chemistry, filtration, circulation, or fine-debris problem. Use this order to narrow it down before adding another product.
The four common causes
Filtration
The filter needs attention
A dirty, damaged, undersized, bypassing, or improperly assembled filter may not capture fine particles.
Circulation
Water is not moving evenly
Low water, clogged baskets, air leaks, valve position, pump issues, or short runtime can leave dead zones.
Fine debris
Particles are suspended
Dust, pollen, swimmers, brushing, or an algae cleanup can temporarily overload the filter.
Do not swim if the bottom or main drain is not clearly visible. Cloudy water is a visibility and rescue hazard.
Troubleshoot in this order
Test free chlorine and pH
Confirm the basics with a reliable kit. Note alkalinity and stabilizer when results do not make sense.
Check flow at the returns
Confirm adequate water level, clean baskets, a fully primed pump, normal valve positions, and no unusual air in the pump basket.
Compare filter pressure
Use the clean baseline for your system. A significant rise suggests cleaning; unusually low pressure can point to restricted intake or bypass.
Brush and vacuum
Move settled material toward the filter and remove heavier debris directly.
Correct one variable at a time
Follow labels, allow adequate circulation, and retest. Clarifiers and flocculants are not substitutes for finding the underlying problem.
Is the water turning green?
Move to the green-pool recovery plan before algae becomes established.