How to Raise Pool Alkalinity: Complete Step-by-Step Guide

Tools & Supplies Needed

Find on Amazon: Taylor K-2006 Pool Test Kit , Pool Grade Sodium Bicarbonate , Digital Pool Water Tester

First, Let's Diagnose Your Alkalinity Problem

Before adding any chemicals, you need to confirm your pool's current total alkalinity (TA) level and understand why it's low. Low alkalinity typically shows these symptoms:

• pH that bounces up and down frequently
• Difficulty maintaining stable chlorine levels
• Etching or pitting on plaster surfaces
• Metallic taste in pool water
• Corrosion of pool equipment

Test your water using a reliable test kit like the Taylor K-2006 or comparable digital tester. Your target alkalinity should be 80-120 ppm for traditional chlorine pools, or 60-80 ppm for salt water generator pools.

Primary Solution: Adding Sodium Bicarbonate

The most effective and economical way to raise alkalinity is using sodium bicarbonate, commonly known as baking soda. However, use pool-grade sodium bicarbonate rather than grocery store baking soda for large adjustments.

Calculating the Correct Dose

Use this precise formula: 1.5 pounds of sodium bicarbonate per 10,000 gallons will raise alkalinity by 10 ppm.

For example, if your 20,000-gallon pool tests at 60 ppm and you want to reach 100 ppm (a 40 ppm increase), you'll need: 20,000 gallons ÷ 10,000 = 2, then 2 × 1.5 pounds × 4 (for 40 ppm increase) = 12 pounds of sodium bicarbonate.

Step-by-Step Application Process

1. Test current levels: Measure both alkalinity and pH before starting. Record these numbers.
2. Calculate needed amount: Use the formula above to determine exact chemical requirements.
3. Prepare the pool: Ensure your circulation system is running and will continue for at least 6 hours.
4. Add chemical gradually: Never dump all the sodium bicarbonate at once. Add no more than 2-3 pounds per 10,000 gallons in a single application.
5. Distribute evenly: Walk around the pool perimeter, broadcasting the sodium bicarbonate across the water surface, focusing on the deep end.
6. Allow circulation: Let the pump run for at least 6 hours to fully dissolve and distribute the chemical.
7. Retest and adjust: Test alkalinity again after 6-8 hours. If you need more, repeat the process.

Alternative Solutions for Specific Situations

When pH is Also Low

If both alkalinity and pH are low, sodium bicarbonate is still your best choice as it raises both parameters. However, if alkalinity is low but pH is already high (above 7.8), consider using sodium sesquicarbonate instead, which has less impact on pH.

For Salt Water Generator Pools

SWG pools should maintain lower alkalinity (60-80 ppm) because the chlorine generation process naturally drives pH up. If your alkalinity is extremely low (below 40 ppm), add sodium bicarbonate conservatively and monitor pH closely.

Common Troubleshooting Issues

Alkalinity Won't Stay Stable

If alkalinity keeps dropping after you raise it, investigate these causes:

• Automatic chlorinator or salt generator producing acidic conditions
• Heavy swimmer load creating organic acid buildup
• Source water with naturally low alkalinity
• Over-shocking with unstabilized chlorine

pH Rises Too High After Treatment

Sodium bicarbonate will raise pH along with alkalinity. If pH exceeds 7.8 after treatment:

1. Stop adding sodium bicarbonate temporarily
2. Add muriatic acid or sodium bisulfate to lower pH to 7.4-7.6
3. Wait 4-6 hours and retest both parameters
4. Continue alkalinity adjustments if needed

Safety Considerations and Best Practices

Safety first: Always add chemicals to water, never water to chemicals. Wear safety glasses and avoid inhaling chemical dust. Store sodium bicarbonate in a cool, dry location away from other pool chemicals.

For ongoing maintenance, test alkalinity weekly and adjust promptly when it drops below your target range. Small, frequent adjustments are easier to manage than large corrections.

Remember that alkalinity acts as a buffer for pH, so stable alkalinity means stable pH, which translates to more effective chlorine and better overall water balance.