How to Lower or Raise pH in a Pool?Updated a month ago
Balancing your pool’s pH is crucial for swimmer comfort, chemical efficiency, and protecting your pool surfaces and equipment. Whether your pH is too high (alkaline) or too low (acidic), here’s how to fix it safely and effectively.
Why pH Matters
Ideal range: 7.2–7.6 (slightly alkaline).
High pH (>7.8): Cloudy water, scaling, reduced chlorine effectiveness.
Low pH (<7.2): Corroded equipment, stinging eyes, and eroded surfaces.
Step 1: Test Your Water
Use a reliable test kit or digital tester to check:
pH level
Total alkalinity (TA) – Aim for 80–120 ppm (stabilises pH).
Always adjust alkalinity first if it’s out of range, as it buffers pH swings.
How to Lower pH (If Too High)
Causes: Hard water, frequent topping up, salt chlorinators, or high alkalinity.
Solutions:
Use pH Decreaser (Sodium Bisulfate):
Add 100–200g per 10,000L (follow product label).
Pour slowly into the deep end with the pump running.
Retest after 4–6 hours and repeat if needed.
Muriatic Acid (Hydrochloric Acid): (Not recommended)
Stronger option for large adjustments.
Wear gloves and goggles! Dilute in water first, then add near return jets.
Update: We have a new Dry Acid pH Decreaser that's safe to handle. So if you're looking to SAFELY decrease your pH levels, don't forget to give it a try.
Pro tip: Aerate the pool (run jets, fountains) to help stabilise pH after lowering.
How to Raise pH (If Too Low)
Causes: Heavy rain, acidic fill water, or overuse of chlorine-based shock.
Solutions:
pH Increaser (Sodium Carbonate):
Add 100–200g per 10,000L (check label for exact dosing).
Broadcast evenly over the pool with the pump running.
Retest after 4–6 hours.
Aeration:
Run water features, point jets upward, or use a fountain to naturally raise pH (slower but chemical-free).
Troubleshooting Common Issues
pH keeps bouncing back: Check alkalinity! Low TA causes pH instability. Raise TA with Water TechniX Alkalinity Up first.
High alkalinity and high pH: Lower alkalinity with the WT Dry acid or muriatic acid, then retest pH.
Saltwater pools: Monitor pH weekly—salt cells often raise pH over time.
Prevent pH Imbalances
Test weekly: Especially after storms, heavy use, or topping up.
Balance alkalinity first: Acts as a pH buffer.
Cover the pool: Reduces dilution from rain and debris.
Avoid chemical overdosing: Add increments slowly and retest.
Safety Tips
Store chemicals in a cool, dry place, away from kids and pets.
Never mix chemicals (e.g., acid and chlorine can create toxic fumes).
Follow labels: Wear gloves and goggles when handling acids.
Need pH Adjusters or Balancers?
Browse our Pool Chemical Collection for pH increasers, decreasers, and alkalinity stabilisers. Pair with a digital test kit for precise adjustments.
Final Tip: Think of pH like Goldilocks’ porridge—it needs to be just right. Stay consistent with testing, and your pool will reward you with clear water and happy swimmers.