Imagine you’ve just returned from a long day at work, ready to dive into your backyard oasis to relax and cool off. However, instead of crystal clear water, you find murky, dirty water that looks less like a pool and more like a science experiment gone wrong. Not exactly the ideal way to unwind after a hard day’s work.
Fortunately, there’s a simple solution to keep your pool looking and feeling clean – Pool Chlorine Tablets.
These hockey-puck-shaped pills may not look impressive, but they pack a powerful punch when it comes to keeping your pool sanitized and free from bacteria, algae, and other impurities.
But how do you determine how many chlorine tablets to use for your pool? Don’t worry, it’s easy with a little basic math.
Here’s a step-by-step guide to calculating the right amount of chlorine tablets for your pool.
How Many Chlorine Tablets for Pool
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 concentration of chlorine 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). If you have an oddly or irregularly shaped pool, using the square footage might be your best option.
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
When adding chlorine tablets to your pool, don’t just toss them directly into the water. Instead, use an inline chlorine dispenser, a 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.
If you don’t have an inline canister, a chlorine floater is a good alternative. Simply place the tablets in the floater and let them dissolve slowly into the water as the floating dispenser moves around the pool.
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 normally 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 a necessary tool 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 that contain a stabilizer (Cyanuric Acid – CYA), which most tablets do actually, then this will help prevent the chlorine from being used too quickly.
Pool Care Handbook and Video Course
When I bought my house with a swimming pool, I knew absolutely nothing about pool care. I just winged it for a while, making many mistakes along the way.
Fortunately, I was recommended Swim University’s Pool Care Handbook and Video Course. I bought it and it was an absolute game-changer.
It was the best money I spent that year. I learned everything from basic cleaning to advanced troubleshooting. Swim University offers a no-quibble refund policy too so what do you have to lose?
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 the pH level, total alkalinity, and calcium hardness of your pool water to ensure that it’s always safe for swimming.
Additionally, it’s a good idea to shock your pool with a higher dose of chlorine every once in a while, 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 in 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?
Provided chlorine tablets are kept in a sealed waterproof container then they should last 3 years or more. Unless you buy a very large supply you are likely to 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. It is the volume of water in the pool that is the 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.
I have had hot tubs for over 20 years and a pool for the last 10 years. I had to learn how to clean, maintain and fix them the hard way. Since then I have helped many friends and neighbors with their pools and now I want to share everything I have learned with you. About Me