A crystal-clear swimming pool is every pool owner’s dream. But when your pool water starts turning green, it’s a sure sign something’s off — and in most cases, the culprit is algae. At Kehlan Pools, we’re here to explain why your pool may be green and how to restore it quickly and safely.
What Turns Pool Water Green?
1. Heavy Rainfall
Rain introduces debris and unbalanced water into your pool. The sudden influx can throw off chemical levels and create a breeding ground for algae.
2. High Temperatures & Heat Waves
Warm, stagnant water accelerates algae growth. During hot summer days, stay consistent with your maintenance to prevent green water.
3. Poor Circulation
If your pool pump or filtration system isn’t running properly, water stagnates — and that’s the perfect environment for algae to take over. Consistent water movement is essential.
4. Neglected Maintenance
Skipping regular brushing, vacuuming, and water testing can invite algae and other contaminants. Pool maintenance isn’t just recommended — it’s required.
5. Copper in the Water
Sometimes, high copper levels — especially from older plumbing or certain algaecides — can cause a green tint when reacting with chlorine. Regular testing helps identify this issue early.
How to Clean a Green Pool: Step-by-Step
Step 1: Brush & Vacuum Thoroughly
Start by brushing the walls, steps, and every corner of the pool to dislodge algae. Use a brush type suited to your pool surface (nylon for fiberglass, steel for concrete). Then vacuum thoroughly.
Step 2: Test pH and Alkalinity
Before shocking, test your water’s pH (ideal: 7.2 – 7.8) and alkalinity (ideal: 80 –120 ppm). Balance these levels to ensure your chemicals work effectively.
Step 3: Double or Triple Shock
Use a high dose of chlorine shock to kill algae. Follow label instructions and wear safety gear. For severe algae, multiple shocks may be needed.
Step 4: Run the Filter
Keep your filtration system running continuously (or for at least 24 – 48 hours) after shocking to help remove dead algae and contaminants.
Step 5: Repeat if Needed
Still seeing green or cloudy water? Repeat the brushing, vacuuming, shocking, and filtering process until clarity returns.
Still Green After Shocking?
Sometimes, green water persists even after shocking. Here’s what to check next:
- Test for Copper: If copper is high, treat with a metal sequestrant and rebalance.
- Retest Chemistry: Even slight imbalances in pH or alkalinity can affect clarity.
- Deep Clean: Make sure every inch of the pool has been properly brushed and vacuumed.
- Inspect or Replace Filter: A clogged or broken filter can’t clean your water effectively.
Common Questions
Can Baking Soda Clear a Green Pool?
No. Baking soda helps adjust pH and alkalinity but doesn’t kill algae. Stick to brushing, shocking, and filtering for best results.
How Fast Can I Clear Green Pool Water?
Depending on the severity, it can take 4 – 5 days to fully restore a green pool. Plan ahead before hosting guests.
Why Your Pool Turns Green in Winter
- Dirty or Damaged Pool Cover: Leaves, pests, and debris entering through a worn cover can cause green water.
- Late Pool Opening: Warmer spring weather creates ideal algae conditions if your pool stays closed too long.
- Lack of Winter Maintenance: Even during the off-season, test your water monthly to avoid a green surprise in spring.
Trust Kehlan Pools for Professional Pool Care
Whether it’s summer maintenance or winter protection, Kehlan Pools offers expert solutions to keep your water clear year-round.
Contact us today for tailored maintenance packages and professional pool care you can trust.