How Many Chlorine Tablets to Keep Your Pool Sparkling?




Struggling to keep your pool water crystal clear and wondering how many chlorine tablets are needed? Proper pool maintenance is essential for a healthy swimming environment, and using the right amount of chlorine is crucial. Knowing how many chlorine tablets to use can be the difference between a sparkling oasis and a murky pond.

Well, we’ll be going over:

  1. Calculate the volume of your pool to determine the amount of chlorine needed.
  2. The general rule of thumb for the number of chlorine tablets required per pool water volume.
  3. Additional considerations and best practices for adding chlorine tablets to your pool for optimal sanitation.

Let’s find out how to effectively use chlorine tablets to maintain a clean and safe pool, ensuring endless summer fun in your backyard paradise.

How many chlorine tablets to add to a pool: To determine the number of chlorine tablets needed, calculate the pool volume and use 1 tablet per 5,000 gallons of water. For example, a 20,000-gallon pool requires 4 tablets. Use an inline chlorine dispenser, floating dispenser, or skimmer for tablet placement. Adjust the frequency based on pool usage and regular maintenance checks.

How Many Chlorine Tablets for Pool

How Many Chlorine Tablets Per Week

Here’s a step-by-step guide to calculating the amount of chlorine tablets to add to your pool weekly.

Step 1: Calculate the pool’s volume

The first step in determining the correct number of 3-inch chlorine tablets is to calculate the volume of your pool. The chlorine concentration needed to keep your pool clean and odorless depends on the pool’s volume, so it’s important to get an accurate measurement.

To calculate the volume, you can either measure the depth, width, and length of your pool or use the cubic footage and multiply it by 7.48 (since a cubic foot holds 7.48 gallons of water). Using the square footage might be your best option if you have an oddly or irregularly shaped pool.

I have produced this handy calculator for square, oblong and round pools:

Swimming Pool Volume Calculator

Please enter your pool shape and dimensions:

Step 2: Round-Up

Once you have calculated the volume of your pool, it’s time to round up to the nearest 5000-gallon interval.

For example, if your pool has a volume of 9,000 gallons, you should round up to 10,000 gallons. Always round up and never round down, as it’s better to add a little extra chlorine than too little.

Step 3: Calculate the number of tablets

Now that you have the rounded volume of your pool, you can calculate how many chlorine tablets per week should be added.

Divide the rounded volume of your pool by 5,000, and you’ll get the number of tablets needed per week.

For example, if your pool has a total rounded volume of 20,000 gallons, you will need to add four chlorine tablets to your pool per week.

Remember to add one tablet for every 5,000 gallons of water, and add a new batch of tablets on the same day every week to keep chlorine levels consistent and suitable for your pool.

Step 4: How to add chlorine tablets

Don’t just toss chlorine tablets directly into the water when adding them to your pool. Instead, use an inline or floating chlorine dispenser, or add them to the pool’s skimmer.

An inline chlorine dispenser is a great option if your pool has one. It holds the chlorine tablets and dispenses them uniformly into the water.

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If you don’t have an inline canister, a chlorine floater is a good alternative. Place the tablets in the floater and let them dissolve slowly into the water as the floating dispenser moves around the pool.

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Lastly, you can add the tablets directly to the pool’s skimmer. Make sure to empty the skimmer basket before adding a new batch of tablets. This is my normal method of adding chlorine tablets to my pool, although it is a controversial topic.

As the pool water will flow over the tablets in the skimmer when the pool pump is running they will dissolve more rapidly than in a floating chlorine dispenser.

See my post Can I Put Chlorine Tablets in My Skimmer Basket?

How often should I add chlorine tablets to my pool?

Generally, you will only need to add tablets to your pool once per week, but perhaps more often if your pool is getting very heavy use.

I usually put 4 chlorine tablets in my skimmer on a Sunday and again the following Sunday and my chlorine levels are normally maintained correctly throughout the week.

Why use chlorine tablets?

Chlorine tablets may not look impressive, but they are necessary for keeping your pool clean and safe. Without them, swimming pools can potentially be dangerous for one’s health, as bacteria and microorganisms can quickly accumulate in stagnant water.

Chlorine tablets work by sanitizing the pool and preventing the growth of algae and bacteria. They also help remove odors and other impurities that may accumulate in the water.

Due to these benefits, the use of chlorine tablets in swimming pools has become standard practice.

Note: If you choose chlorine tablets containing a stabilizer (Cyanuric Acid – CYA), which most tablets do, this will help prevent chlorine from being used too quickly.

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Using chlorine tablets is a convenient and cost-effective way to maintain your pool’s cleanliness and safety. By following the steps outlined above, you can calculate the right amount of tablets needed to keep your pool in tip-top shape.

It’s important to note that while chlorine tablets are effective in keeping your pool clean, they are not a substitute for regular maintenance. You still need to keep an eye on your pool water’s pH level, total alkalinity, and calcium hardness to ensure it’s always safe for swimming.

Additionally, it’s a good idea to shock your pool with a higher dose of chlorine occasionally, especially after heavy use or during hot weather. This helps to kill any bacteria or algae that might have formed in the water.

Chlorine tablets FAQs

How long should 3 chlorine tablets last?

How long 3 chlorine tablets will last in a pool depends on whether they are in an inline chlorine dispenser, a floating dispenser, or the skimmer basket. They will probably last 4-5 days in a floating dispenser or 3-4 days in either of the other two.

How long do chlorine tablets last in a pool?

If chlorine tablets are kept in a sealed waterproof container, they should last 3 years or more. Unless you buy a large supply, you will likely use them long before they become this old.

How many chlorine tablets for 10ft pool?

Although many people ask this question, the length of a pool does not determine how many chlorine tablets should be added. The volume of water in the pool is an important factor. So you should multiply the length, by the width by the depth in feet and then multiply that figure by 7.48 to find out the volume in gallons.

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