Quick Answer
Fix cloudy pool water by immediately shocking to proper levels based on your CYA, running your filter 24/7, and maintaining proper chemical balance until water clears in 24-48 hours.
Tools & Supplies Needed
Find on Amazon: Taylor K-2006C Complete Pool Test Kit , Liquid Chlorine Pool Shock , Muriatic Acid Pool pH Reducer
Quick Solution
The fastest way to clear cloudy pool water is to shock your pool to the proper level based on your CYA (stabilizer) level and run your filter continuously. Most cloudy water clears within 24-48 hours with proper shocking and filtration. Add liquid chlorine to reach shock level, run your pump 24/7, backwash when pressure rises 8-10 psi, and maintain shock level until water is crystal clear.
Immediate Action Steps
- Test your water chemistry - Use a quality test kit like Taylor K-2006C to measure Free Chlorine (FC), pH, Total Alkalinity (TA), and Cyanuric Acid (CYA). These numbers determine your exact treatment plan.
- Calculate shock level - Your shock level depends on CYA. For 30 ppm CYA, shock to 12 ppm FC. For 50 ppm CYA, shock to 20 ppm FC. Use the FC/CYA chart: divide CYA by 10, then multiply by 4 for minimum shock level.
- Add liquid chlorine immediately - Use 12.5% liquid chlorine (sodium hypochlorite), not granular shock. Add 1 gallon of liquid chlorine per 10,000 gallons to raise FC by approximately 10 ppm. Calculate your exact needs and add it all at once.
- Run filter continuously - Set your pump to run 24/7 until water clears. Cloudy water means your filter is working overtime to capture particles. Don't give it a break until the job is done.
- Backwash frequently - For sand and DE filters, backwash when pressure gauge rises 8-10 psi above clean starting pressure. For cartridge filters, rinse every 12-24 hours during treatment.
Maintain Shock Level
This is the critical step most people miss. Test your FC every 4-6 hours and add more liquid chlorine to maintain shock level. Cloudy water consumes chlorine rapidly as it oxidizes contaminants. If FC drops below shock level, the process stalls and takes much longer.
Add liquid chlorine in smaller doses throughout the day rather than one large dose. For a 20,000-gallon pool maintaining 15 ppm FC, you might need to add 1/2 gallon every 6 hours initially. As water clears, chlorine consumption decreases.
Fix pH and Alkalinity Issues
Cloudy water often indicates pH problems. Test and adjust pH to 7.4-7.6 for optimal chlorine effectiveness. If pH is above 7.8, add muriatic acid. Use 1 quart of muriatic acid per 20,000 gallons to lower pH by approximately 0.2.
Total Alkalinity should be 80-120 ppm for most pools (60-80 for salt water generators). Low TA causes pH to bounce around, making it hard to maintain proper chlorine levels. Add sodium bicarbonate (baking soda) at 1.5 lbs per 10,000 gallons to raise TA by 10 ppm.
Address Root Causes
While shocking clears cloudy water, identify why it happened to prevent recurrence:
- Poor filtration - Run pump 8-12 hours daily minimum, more in hot weather or heavy use
- Low chlorine levels - Maintain FC at proper level for your CYA year-round
- High CYA levels - If CYA exceeds 80 ppm, partially drain and refill pool
- Dirty filter media - Clean cartridges monthly, replace sand every 5-7 years, replace DE powder after each backwash
- Poor water circulation - Ensure return jets create circulation to all pool areas
When Water Should Clear
Properly shocked pools with good filtration typically clear within 24-48 hours. If water isn't noticeably clearer after 24 hours, check these issues:
- FC level dropped below shock level - test and add more chlorine
- Filter is overwhelmed - clean or backwash more frequently
- pH is too high - chlorine is less effective above 7.6
- CYA level is too high - requiring higher shock levels
Safety Warnings
Never swim in cloudy water - you can't see the bottom, creating drowning risk. Wait until water is crystal clear before allowing swimming.
Add chemicals safely - Pour liquid chlorine slowly around pool perimeter with pump running. Never mix different chemicals together. Store chemicals in cool, dry location away from other pool chemicals.
Expected Timeline and Costs
Most cloudy water situations resolve in 1-3 days with proper treatment. Severely cloudy or green water may take 5-7 days. Budget $20-40 for liquid chlorine and test kit reagents for typical cloudy water treatment. Prevention through regular maintenance costs far less than emergency treatments.
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