Your pool’s water chemistry depends heavily on two critical factors: pH level and total alkalinity. When either is off, it can lead to skin and eye irritation, corrosion of equipment, and cloudy water.
At M&M Pool & Spa, we help homeowners and property managers adjust these levels correctly to protect both swimmers and pool systems.
✅ Quick Summary: pH & Alkalinity Basics
- Ideal pH: 7.4 to 7.6
- Ideal Total Alkalinity: 80–120 ppm
- High or low levels cause damage, discomfort, and instability
- Use pH Up/Down and sodium bicarbonate or acid to adjust
- Always test water before and after adjustments
1. What Is pH and Why Is It Important?
The pH level tells you how acidic or basic your pool water is:
- Low pH (< 7.2) = acidic = skin irritation, corrosion
- High pH (> 7.8) = basic = cloudy water, reduced chlorine power
The sweet spot is 7.4 to 7.6, close to human tears and ideal for swimmer comfort.
2. What Is Total Alkalinity?
Total alkalinity acts as a buffer for pH—keeping it from fluctuating wildly. If alkalinity is too low, pH becomes unstable. If it’s too high, adjusting pH becomes difficult.
- Ideal range: 80–120 ppm
- Measured in parts per million (ppm) during pool water testing
🔗 Know More: Read our full Guide to Testing Pool Water Levels for weekly testing recommendations.
3. Tools & Chemicals You’ll Need
- Test kit or digital reader
- pH increaser (sodium carbonate)
- pH decreaser (muriatic acid or sodium bisulfate)
- Alkalinity increaser (sodium bicarbonate)
- Protective gloves and eyewear
4. How to Adjust pH and Alkalinity
If pH is too low (<7.2):
- Add pH increaser (sodium carbonate)
- Circulate water for 4–6 hours
- Retest and repeat as needed
If pH is too high (>7.8):
- Add pH decreaser (muriatic acid or dry acid)
- Pour slowly near return jets with pump running
- Retest after 4–6 hours
If Alkalinity is too low (<80 ppm):
- Add sodium bicarbonate (baking soda)
- 1.5 lbs per 10,000 gallons raises TA by 10 ppm
- Add in stages, retesting between applications
If Alkalinity is too high (>120 ppm):
- Add muriatic acid in small doses
- Lower pH gradually while TA drops
- Aerate water to stabilize pH afterward
5. Tips for Safe and Accurate Adjustments
- Always adjust alkalinity first, then pH
- Never mix chemicals directly—add one at a time
- Wear protective gear
- Follow label dosing instructions carefully
- Wait 4–6 hours between doses and retest
External Link: For safety guidelines, refer to EPA’s chemical safety fact sheet for pool chemical handling.
Conclusion: Consistent Balance, Cleaner Water
Keeping pH and alkalinity in range is essential for equipment longevity, swimmer comfort, and effective sanitization. If your readings are constantly off, or adjustments don’t hold, let the experts handle it.
