Pool pH Won't Stay Balanced
pH keeps drifting high or low despite constant adjustments
Quick Answer
pH instability is usually caused by incorrect total alkalinity (80% of cases). Low alkalinity (<80 ppm) makes pH bounce rapidly, while high alkalinity (>150 ppm) makes pH drift upward and resist adjustment. Fix alkalinity FIRST, then adjust pH. Also check chlorine type - liquid chlorine raises pH, trichlor tablets lower pH over time.
Understanding pH Stability
pH vs. Total Alkalinity
pH measures how acidic or basic water is RIGHT NOW. Total alkalinity measures the water's ability to RESIST pH changes. Think of alkalinity as pH's "shock absorber" - without proper alkalinity, pH will constantly bounce around no matter how much pH adjuster you add.
Why pH Drifts
- • Wrong alkalinity: Too low or too high prevents pH stability
- • Chemical imbalance: Chlorine type pushing pH up or down
- • Water demand: Pool consuming chemicals faster than normal
- • External factors: Rain, heavy use, equipment issues
- • Poor testing: Inaccurate readings leading to wrong adjustments
Proper pH Range
Total Alkalinity: The Key to pH Stability
Low Alkalinity (<80 ppm)
pH bounces everywhere: No buffering capacity means pH swings wildly with any chemical addition.
Symptoms: pH changes dramatically with small chemical additions, impossible to maintain stable levels.
What Happens:
- • pH swings from 6.8 to 8.2 overnight
- • Adding pH up or down causes wild swings
- • Chlorine becomes ineffective
- • Equipment and surface corrosion
Solution:
- • Add sodium bicarbonate (baking soda)
- • Raise alkalinity to 80-120 ppm first
- • THEN adjust pH to 7.2-7.6
- • pH will now stay stable
High Alkalinity (>150 ppm)
pH drifts high and won't budge: Too much buffering capacity locks pH in alkaline range.
Symptoms: pH constantly rises to 8.0+, adding pH down has little effect, requires large amounts of acid.
What Happens:
- • pH slowly climbs to 8.0+ daily
- • pH down has minimal temporary effect
- • Scale formation on surfaces
- • Cloudy water from calcium precipitation
Solution:
- • Add muriatic acid to lower alkalinity
- • Lower alkalinity to 80-120 ppm range
- • Aerate pool to raise pH after acid
- • Process takes several days
Proper Alkalinity (80-120 ppm)
pH stays stable: Right amount of buffering capacity maintains pH in proper range.
Goal: pH adjustments work properly and last several days to a week between corrections.
Benefits:
- • pH changes slowly and predictably
- • Small adjustments have lasting effect
- • Chlorine works at peak efficiency
- • Equipment protected from corrosion
Maintenance:
- • Test alkalinity weekly
- • Adjust pH as needed (usually weekly)
- • Monitor chlorine type effects
- • Professional service prevents problems
What's Pushing Your pH Up or Down?
Chlorine Type Effects
Different chlorine sources have dramatically different effects on pH over time.
Liquid Chlorine (Sodium Hypochlorite)
⬆️ Raises pH
pH: 13+ when pure, constantly pushes pool pH upward
Trichlor Tablets
⬇️ Lowers pH
pH: 2.8, acidic tablets gradually lower pH and alkalinity
Cal-Hypo Shock
➡️ Neutral
pH: 11.8, raises pH temporarily during shock only
Local Area pH Challenges
The Southlake, Westlake, Grapevine area water and climate create unique pH stability challenges.
Hard Water Issues:
- • High calcium hardness (300-500+ ppm)
- • High total alkalinity in fill water
- • Scaling tendency at high pH
- • Calcium precipitation causing cloudiness
Environmental Factors:
- • Heavy summer pool usage
- • Frequent thunderstorms diluting chemistry
- • High evaporation concentrating minerals
- • Wind blowing debris and contaminants
Other pH Affecting Factors
Heavy Usage
- • Body oils and lotions
- • Organic contamination
- • Urine and sweat
- • Increased chlorine demand
Weather Events
- • Rain diluting chemistry
- • Wind-blown debris
- • Temperature affecting chemical activity
- • UV degradation of chlorine
Equipment Issues
- • Salt chlorinator cells raising pH
- • Ozone systems affecting chemistry
- • Chemical feeders out of adjustment
- • Aeration from water features
Chemical Safety for pH Adjustment
- •Never mix different chemicals directly - add one at a time
- •Wait 4-6 hours between adding different chemicals
- •Always add acid to water, never water to acid
- •Use protective equipment when handling chemicals
- •Store chemicals properly in cool, dry location
- •Keep pool running during chemical adjustment process
Step-by-Step pH Balancing Process
Phase 1: Test and Evaluate (Day 1)
Test All Chemistry
pH, Alk, Hardness, CYA
Record Results
Document trends
Identify Problem
Root cause analysis
Calculate Chemicals
Exact amounts needed
Fix Alkalinity First
80-120 ppm target
Phase 2: Chemical Adjustment (Days 2-3)
If Alkalinity is Low (<80 ppm):
- Add sodium bicarbonate (baking soda)
- 1.5 lbs per 10,000 gallons raises alk by ~10 ppm
- Wait 6+ hours for full circulation
- Retest alkalinity and pH
- Adjust pH to 7.2-7.6 range
If Alkalinity is High (>150 ppm):
- Add muriatic acid to lower alkalinity
- 1 quart per 10,000 gallons lowers alk ~10 ppm
- Pour acid over return jets (never in skimmer)
- Wait 6+ hours, then aerate to raise pH
- Repeat process until alkalinity is 80-120 ppm
Phase 3: Monitoring and Maintenance (Ongoing)
Success metric: pH should stay in range for 3-7 days between adjustments.
Daily (First Week):
- • Test pH and alkalinity
- • Document any drift patterns
- • Make small adjustments as needed
- • Monitor chlorine type effects
Weekly (Ongoing):
- • Complete chemistry testing
- • Adjust pH if outside range
- • Monitor alkalinity stability
- • Evaluate chlorine type/method
Call Professional If:
- • pH changes daily despite proper alkalinity
- • Multiple chemical adjustments not working
- • Water balance problems persist
- • Scaling or corrosion appears
Professional Water Chemistry Analysis
Test Complete Water Chemistry
Get full picture of water balance, not just pH
⚠️ Warning: Test strips often inaccurate for troubleshooting pH problems
Evaluate Total Alkalinity
Alkalinity is the key to pH stability
⚠️ Warning: Fixing alkalinity first is critical - pH adjustments won't stick without proper buffering
Identify Chemical Sources Affecting pH
Determine what's causing pH to drift
⚠️ Warning: Some chemicals continuously push pH in one direction - address the source
Check for External Factors
Environmental and equipment issues affecting pH
⚠️ Warning: New plaster pools have unique chemistry challenges for 30-90 days
Calculate Proper Chemical Adjustments
Systematic approach to achieve stable pH
⚠️ Warning: Large chemical adjustments can damage pool surfaces and equipment
pH Balancing and Chemistry Correction Costs
🔧 DIY Attempt
⚠️ Risks:
- • Over-correcting chemistry causing expensive damage
- • Using wrong chemicals or amounts making problems worse
- • Missing root cause leading to recurring problems
- • Equipment damage from improper pH levels
👷 Professional Service
✅ Includes:
- • Complete water chemistry analysis and diagnosis
- • Professional-grade chemicals and precise dosing
- • Expert identification of root causes
- • Systematic correction of all chemistry parameters
- • Follow-up testing and adjustment
- • Prevention plan and maintenance recommendations
Detailed Cost Breakdown
| Item/Service | Low | High |
|---|---|---|
| Chemistry testing and analysis | $50 | $100 |
| Alkalinity adjustment chemicals | $25 | $75 |
| pH adjustment and balancing | $25 | $50 |
| Professional water balancing service | $100 | $250 |
| Total Range | $200 | $475 |
💰 Value Tip: CoOpPools offers transparent pricing with no hidden fees. Our worker-owned model means fair prices and invested service.
Preventing pH Problems
Weekly Maintenance
- • Test alkalinity weekly: Maintain 80-120 ppm range
- • Monitor chlorine type effects: Balance convenience vs pH impact
- • Test complete chemistry: pH, alkalinity, hardness, CYA
- • Small frequent adjustments: Better than large corrections
- • Document trends: Track patterns to predict needs
- • Professional service: Weekly or bi-weekly maintenance
Local Area Specific Prevention
- • Hard water management: Monitor calcium levels monthly
- • Storm preparation: Test chemistry after heavy rain
- • Summer usage adjustments: Increase testing frequency
- • Partial water replacement: Dilute high mineral content
- • Quality test kit: Invest in accurate testing equipment
- • Professional startup: Annual chemistry reset and balancing
Need Professional Help?
Persistent pH problems often indicate complex water balance issues that require professional expertise. Our water chemistry specialists can quickly identify root causes and implement lasting solutions to keep your pool chemistry stable and balanced.
Mention "pH balancing and water chemistry" when calling for faster service