How to Increase Pool Alkalinity - Step-by-Step Guide

Tools & Supplies Needed

Find on Amazon: Taylor K-2006 Complete Test Kit , Sodium Bicarbonate Pool Grade , Pool Chemical Mixing Bucket

First, Let's Diagnose Your Alkalinity Problem

Before we jump into raising your pool's alkalinity, we need to confirm you actually have a low alkalinity issue. Total alkalinity (TA) acts as a pH buffer in your pool water, and proper levels are crucial for water balance and swimmer comfort.

Test your water using a reliable test kit - I recommend the Taylor K-2006 or Taylor K-2005 for accurate readings. Your target total alkalinity should be:

• Salt water pools: 60-80 ppm
• Traditional chlorine pools: 80-120 ppm
• Plaster pools: 80-120 ppm (higher end preferred)

If your alkalinity is below these ranges, you'll likely notice pH that's difficult to maintain, frequent pH swings, or water that feels "sharp" to swimmers. Low alkalinity can also cause equipment corrosion and surface etching.

Calculate Your Sodium Bicarbonate Dosage

Sodium bicarbonate (baking soda) is the safest and most effective way to raise pool alkalinity. Here's the dosing formula you need:

1.5 pounds of sodium bicarbonate per 10,000 gallons raises total alkalinity by 10 ppm

Let's work through an example: If you have a 20,000-gallon pool with alkalinity at 60 ppm and you want to reach 100 ppm, you need to raise it by 40 ppm. Your calculation would be:

• 40 ppm increase needed ÷ 10 ppm per dose = 4 doses required
• 4 doses × 1.5 lbs = 6 lbs of sodium bicarbonate
• Adjust for pool size: 6 lbs × (20,000 ÷ 10,000) = 12 lbs total

Safety Warning: Never add more than 2 lbs per 10,000 gallons at one time, as this can cause cloudy water and pH spikes.

Step-by-Step Application Process

1. Turn on your circulation system - Your pump should run throughout the entire process to ensure even distribution.
2. Pre-dissolve the sodium bicarbonate - Fill a 5-gallon bucket with pool water and slowly add your calculated dose of baking soda while stirring. This prevents undissolved powder from settling on your pool surfaces.
3. Pour around the pool perimeter - Walk around your pool while slowly pouring the dissolved solution, focusing on areas with good water movement like near return jets.
4. Brush if necessary - If any undissolved powder settles on surfaces, brush it gently to help it dissolve completely.
5. Continue circulation for 6 hours minimum - This allows the chemical to fully integrate and stabilize in your water.
6. Retest your water - After 6 hours, test both alkalinity and pH levels to confirm your results.

Managing pH During Alkalinity Adjustment

Here's where many pool owners run into trouble: sodium bicarbonate will raise both alkalinity and pH. If your pH climbs above 7.8 during this process, you'll need to bring it down with muriatic acid before continuing.

The key is patience. Add your alkalinity increaser in smaller doses (1-1.5 lbs per 10,000 gallons), test after 6 hours, and adjust pH if needed before adding more. This prevents the frustrating cycle of constantly chasing chemical balance.

If you need to lower pH during this process, use muriatic acid at a rate of 1 cup per 10,000 gallons to lower pH by approximately 0.2 units. Always add acid to water, never water to acid, and pour into the deep end with your pump running.

Troubleshooting Common Issues

Cloudy water after adding baking soda: This usually means you added too much too quickly. Continue running your filter, and the cloudiness should clear within 24-48 hours. Consider adding a clarifier if cloudiness persists.

pH keeps climbing: This is normal when raising alkalinity. Lower pH with small amounts of muriatic acid between alkalinity additions, and don't rush the process.

Alkalinity won't stay up: If alkalinity drops quickly after raising it, check for excessive aeration (waterfalls, fountains) or ensure you're not over-chlorinating, as high chlorine levels can affect alkalinity readings.

Maintenance and Prevention Tips

Once you achieve proper alkalinity levels, maintain them by testing weekly and making small adjustments as needed. Heavy rain, swimmer load, and chemical additions all affect alkalinity over time.

Keep sodium bicarbonate on hand for minor adjustments - it's much cheaper to buy in bulk from pool supply stores than grocery store baking soda, though both are chemically identical.

Remember that proper alkalinity makes pH management much easier, so getting this right will save you time and frustration with overall water balance. Always adjust alkalinity first, then pH, then other chemical levels for best results.