Water Chemistry & Treatment — PoolPad guides
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Water Chemistry & Treatment

Read pool test results, adjust pH, alkalinity, chlorine, and other sanitizers, then track down algae, cloudiness, and stains.

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Water Chemistry & Treatment Guides

Pick the setup question, maintenance job, or symptom you need to handle next.

How Much of Each Pool Chemical to Add

How Much of Each Pool Chemical to Add

A dosing guide for balancing pool chlorine, pH, and alkalinity and calculating how much chemical to add.

How to Shock a Pool: Products, Dosing and Safety

How to Shock a Pool: Products, Dosing and Safety

How to choose, dose, and safely apply pool shock to treat algae and restore sanitary water.

Cyanuric Acid in Pools: Purpose and Recommended Levels

Cyanuric Acid in Pools: Purpose and Recommended Levels

How cyanuric acid protects chlorine from sunlight, plus guidance for testing and adjusting its level.

How to Raise Free Chlorine in Your Pool

How to Raise Free Chlorine in Your Pool

Methods for raising free chlorine, choosing a chlorinating product, and checking levels before swimming.

Green Pool: How to Clear It in 24 Hours

Green Pool: How to Clear It in 24 Hours

A 24-hour treatment plan for diagnosing green water, killing algae, filtering debris, and rebalancing pool chemistry.

How to Raise Cyanuric Acid in Your Pool

How to Raise Cyanuric Acid in Your Pool

Methods for raising cyanuric acid to protect chlorine from sunlight, with dosing and retesting guidance.

How to Lower Alkalinity in a Pool

How to Lower Alkalinity in a Pool

A process for lowering high pool alkalinity, retesting the water, and correcting related pH changes.

Pool Algae: How to Remove and Prevent It

Pool Algae: How to Remove and Prevent It

How to identify, treat, and prevent common pool algae through cleaning, filtration, and water care.

How to Lower pH in a Pool

How to Lower pH in a Pool

How to lower pool pH with muriatic acid or sodium bisulfate, including dosing and safe handling.

How to Add Chlorine to a Pool: Tablets, Granules & Liquid

How to Add Chlorine to a Pool: Tablets, Granules & Liquid

How to add chlorine tablets, granules, or liquid and verify safe pool chlorine levels.

How Much Chlorine to Add to Your Pool

How Much Chlorine to Add to Your Pool

Pool chlorine dosing guidance based on water volume, product type, current levels, and maintenance needs.

Can You Use Bleach in a Pool? Safety and Dosing

Can You Use Bleach in a Pool? Safety and Dosing

Household bleach for pool sanitation, including concentration, dosage, handling, and compatibility considerations.

Calcium Hypochlorite Pool Shock: Uses and Dosing

Calcium Hypochlorite Pool Shock: Uses and Dosing

Calcium hypochlorite pool shock explained, including its benefits, application, and handling considerations.

How to Remove Mustard Algae from a Pool

How to Remove Mustard Algae from a Pool

How to identify and remove mustard algae, treat affected surfaces, and reduce the chance of recurrence.

Pool Water Testing: How to Test pH, Chlorine & More

Pool Water Testing: How to Test pH, Chlorine & More

Pool water testing guidance for measuring and balancing pH, chlorine, and alkalinity.

Clear Cloudy Pool Water: Flocculant vs. Clarifier Explained

Clear Cloudy Pool Water: Flocculant vs. Clarifier Explained

Pool flocculant and clarifier compared by purpose, application, cleanup, and the water problems each treats.

Pool Phosphates: How They Affect Water & Algae

Pool Phosphates: How They Affect Water & Algae

How phosphates contribute to algae growth, how to test for them, and when phosphate removal may help.

Pool Clarifier vs. Flocculant: Uses and Differences

Pool Clarifier vs. Flocculant: Uses and Differences

Pool clarifiers and flocculants compared by how they work, when to use them, and the cleanup each requires.

Best Pool Shock: Types, Ingredients and Uses

Best Pool Shock: Types, Ingredients and Uses

Pool shock types compared by active ingredient, use case, dosing, and maintenance considerations.

Non-Chlorine Pool Shock: Benefits and Uses

Non-Chlorine Pool Shock: Benefits and Uses

Non-chlorine pool shock compared with chlorine shock by oxidizing action, use cases, limitations, and swimmer wait time.

How to Lower Cyanuric Acid in Your Pool

How to Lower Cyanuric Acid in Your Pool

How to confirm and lower high cyanuric acid, then rebalance chlorine and prevent levels from climbing again.

When Is It Safe to Swim After Shocking Your Pool?

When Is It Safe to Swim After Shocking Your Pool?

How long to wait after shocking a pool based on product instructions, chlorine readings, water clarity, and safety checks.

Pool Test Strips: How to Read & Use Them

Pool Test Strips: How to Read & Use Them

Pool test strip instructions for measuring pH, chlorine, and alkalinity and interpreting each color reading.

Pool Test Kits: How to Choose the Right One

Pool Test Kits: How to Choose the Right One

Digital and manual pool test kits compared by measured values, accuracy, supplies, testing process, and cost.

Pool Chlorine Tablets: Types, Dosing and Placement

Pool Chlorine Tablets: Types, Dosing and Placement

How to choose, place, and dose chlorine tablets while protecting pool surfaces and maintaining safe sanitizer levels.

Muriatic Acid for Pools: How to Use It Safely

Muriatic Acid for Pools: How to Use It Safely

How to use muriatic acid to lower pool pH and alkalinity, including dosing, dilution, and handling precautions.

How Much Pool Shock to Use: A Dosing Guide

How Much Pool Shock to Use: A Dosing Guide

How to calculate pool shock dosage from water volume, product strength, chlorine demand, and treatment goal.

Pool Calcium Hardness: How to Balance It

Pool Calcium Hardness: How to Balance It

Pool calcium hardness ranges, testing, and adjustment methods for preventing scale and corrosion.

Black Algae in Pools: Removal and Prevention

Black Algae in Pools: Removal and Prevention

How to identify and remove black algae with brushing, chlorine treatment, filtration, and follow-up prevention.

How to Safely Lower Chlorine Levels in Your Pool

How to Safely Lower Chlorine Levels in Your Pool

How to lower excess pool chlorine using sunlight, dilution, or a neutralizer, then confirm a safe level.

Pool Chemistry: How to Balance pH, Chlorine & More

Pool Chemistry: How to Balance pH, Chlorine & More

Pool chemistry fundamentals for balancing pH, chlorine, alkalinity, calcium hardness, and stabilizer.

Baquacil Pool Care: How It Works and Maintenance

Baquacil Pool Care: How It Works and Maintenance

Baquacil pool sanitation explained, including system components, routine maintenance, compatibility, and tradeoffs.

Pool Mineral Systems: How They Work & Benefits

Pool Mineral Systems: How They Work & Benefits

Pool mineral systems explained, including sanitizer reduction, components, maintenance, costs, and limitations.

Best Pool Chemical Calculator Apps of 2026

Best Pool Chemical Calculator Apps of 2026

Pool chemical calculator apps compared for dosing, water-balance tracking, supported chemicals, and ease of use.

Chlorine-Free Pool Options: Types and Tradeoffs

Chlorine-Free Pool Options: Types and Tradeoffs

Saltwater, UV, mineral, and other low-chlorine pool sanitation options, with maintenance and limitation notes.

Liquid vs. Granular Chlorine: Differences and Uses

Liquid vs. Granular Chlorine: Differences and Uses

Liquid chlorine and chlorine granules compared for strength, dosing, storage, cost, and routine pool care.

Pool Stabilizer: What It Is & How to Use It

Pool Stabilizer: What It Is & How to Use It

How pool stabilizer protects chlorine, how to test and adjust it, and how to troubleshoot high or low levels.

Algaecide for Pools: Types, Uses & How It Works

Algaecide for Pools: Types, Uses & How It Works

Pool algaecide types, when to use them, application guidance, and common limits and misconceptions.

Baking Soda in Pool: How to Raise Alkalinity

Baking Soda in Pool: How to Raise Alkalinity

Baking soda dosing for raising pool alkalinity, with volume calculations, application, retesting, and pH considerations.

Pool Ionizers: How They Work, Benefits and Limits

Pool Ionizers: How They Work, Benefits and Limits

Pool ionizer operation, claimed chlorine reduction, maintenance requirements, costs, and sanitation limitations.

Pool Nitrates: How to Test, Lower & Prevent Them

Pool Nitrates: How to Test, Lower & Prevent Them

How nitrates enter pool water, how to test for them, and steps for limiting algae when levels are elevated.

Chlorine Lock: What It Is & How to Fix It

Chlorine Lock: What It Is & How to Fix It

Causes of chlorine lock and chlorine demand in pools, with testing and correction steps for each.

Free vs. Combined Chlorine: Test Results Explained

Free vs. Combined Chlorine: Test Results Explained

The difference between total and free chlorine, how to interpret test results, and what combined chlorine indicates.

Stabilized vs. Unstabilized Chlorine: Key Differences

Stabilized vs. Unstabilized Chlorine: Key Differences

Stabilized and unstabilized chlorine compared by composition, sunlight protection, use cases, and effects on cyanuric acid.