How to Prevent Pool Green Water After Rain?Updated a month ago
Rainwater can introduce contaminants, dilute chemicals, and spark algae growth—turning your pool into a swampy mess. Here’s how to protect your pool before, during, and after storms.
Pre-Rain Prevention
Cover Up: Use a pool cover to block debris and minimise chemical dilution.
Pre-Shock: Add pool shock 24 hours before heavy rain to boost chlorine levels.
Balance Chemistry:
pH: 7.2–7.6 (prevents algae-friendly conditions).
Chlorine: 2–3 ppm (higher than usual to offset dilution).
Alkalinity: 80–120 ppm (stabilises pH).
Add Algaecide: A preventative dose of good pool algaecide stops spores from blooming.
Post-Rain Action Plan
Remove Debris: Skim leaves, dirt, and organic matter ASAP.
Test Pool Water: Check chlorine, pH, and alkalinity—rebalance if needed.
Shock Again: Use chlorine shock (double dose if water is cloudy).
Brush & Vacuum: Scrub walls and floors to disrupt algae clinging to surfaces.
Clean Filters: Backwash sand/DE filters or rinse cartridges to clear trapped contaminants.
Long-Term Tips
Install Overflow Relief: Redirect excess rainwater to prevent dilution (use a submersible pump or venturi pump if needed).
Check Drainage: Ensure runoff (e.g., garden soil, mulch) doesn’t flow into the pool.
Trim Overhanging Trees: Reduce leaf litter and organic debris.
Use a Phosphate Remover: Rainwater often contains phosphates (algae food)—neutralise them monthly.
Troubleshooting Persistent Green Water
Still green after shocking? Test for phosphates or metals (common in bore water).
Cloudy water? Add a clarifier to clump particles for easy filtering. (Try our new clarifier tablets)
Filter struggling? Soak cartridges or grids in filter cleaner to dissolve oils and grime.
Need Rain-Ready Supplies?
Stock up with our pool maintenance range, including all of your essential post storm cleaning tools and kits. Pair with a reliable test kit to stay ahead of storms.
Final Tip: Consistency beats chaos! A little prep before rain saves hours of cleanup.