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7 best chlorine tablets for pool

Which chlorine tablets are best?

Having a pool in your yard or your house is a great amenity to have in your daily life. But it’s no secret that swimming pools require maintenance. Not only is it more pleasant to swim in a clean, well-maintained pool, it’s also crucial for your health. Pool water can quickly become polluted with all kinds of bacteria and algae, some of which can be extremely dangerous.

Chlorine tablets provide a quick, simple method for keeping pool water clear and clean.  

What are chlorine tablets?

Chlorine is a powerful chemical that's usually in gas form at room temperature. This form can be dangerous: when people come into contact with concentrated chlorine gas, it causes severe burning to the respiratory system, skin and eyes.

However, chlorine is extremely effective at killing off dangerous bacteria in the water. It’s used in cleaning products, public sanitation and water treatment. It’s also commonly used in swimming pools to keep them safe.

As home swimming pools became more commonplace, people needed a simple and safe way to treat the water with chemicals. So chlorine is now sold in its solid form as tablets to make it easy and affordable to treat home pools' water.

Chlorine tablets are less strong than pure chlorine gas, but they’re still very powerful. You’ll notice most chlorine tablets are labeled with an “available chlorine” percentage. For example, if a chlorine tablet has 90% chlorine available, this means the tablets are 90% as strong as chlorine gas.   

How do chlorine tablets clean pool water?

Chlorine needs to be dispersed through the water to clean it properly. As the tablets dissolve in the water, the chlorine attacks and breaks down contaminants such as bacteria. 

It does this by breaking down into hypochlorous acid and hypochlorite ions. These kill germs by oxidizing them and breaking down the chemical bonds that make up their structure. Hypochlorous acid does this on contact with the molecules. Hypochlorite ions have the same effect over a longer period.

How to use chlorine tablets

Chlorine tablets typically come in two sizes: 1-inch or 2-inch tablets. You can buy containers of tablets in various amounts depending on how often you’ll need to use them.

A 1-inch tablet cleans about 5,000 gallons of water, so if you have a 10,000-gallon pool you would use two tablets at the same time.

If you have an outdoor pool, stabilized chlorine tablets are best. Chlorine can burn under the sun’s ultraviolet rays, which means the tablets become less effective. Stabilized tablets contain cyanuric acid to protect the chlorine from these rays.

Chlorine tablets should not be thrown directly into your pool. This can cause staining on the pool's floor and the chemicals won’t distribute properly throughout the water. Instead, you can use a pool floater or add the tablets to your pool skimmer.

You also can buy an automatic chlorinator. With this machine, you simply load chlorine tablets inside, then select how quickly you want to dispense chlorine into the pool water. While more expensive, this is a more convenient “set it and forget it” option.

How often you add chlorine tablets to your pool can vary. For example, climate and weather can affect how quickly bacteria build up in an outdoor pool. Even with indoor pools, frequent use by a large number of people can mean it needs chlorine tablets more often. A good rule of thumb is once per week.

Best chlorine tablets to buy for your pool

Clorox Pool & Spa XtraBlue Long-Lasting Chlorinating Tablets

These tablets stop algae, kill bacteria, provide surface protection and give water a silky-smooth look and feel. All you need to do is use a tablet weekly after pH testing to see how acid or alkaline the water is, so they’re very simple to use.

Sold by Amazon

Poolwell Pool and Spa Chlorine Tablets

These tablets give pools a silky-smooth water effect and surface protection, preventing itchy skin and eyes while preventing green algae, bacteria and hard water buildup. They are perfect for floaters or automatic chlorine feeders, with just one tablet needed per 10,000 gallons of water.

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Doheny's 3-Inch Swimming Pool Chlorine Tablets

These fast-acting tablets contain 99% stabilized chlorine to keep your pool clean, clear and free of harmful bacteria. The child-resistant packaging means they are safe to store and the 8-ounce tablets are compressed to reduce dissolve rates and prolong shelf life.

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Pool Mate Jumbo Swimming Pool Chlorine Tabs

These jumbo chlorine tabs are powerful and long-lasting due to their slow dissolve and release rate. Each 8-ounce tablet is stabilized to protect against UV rays, and the recommended dosage is between one and three tablets per week.

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In the Swim 3-Inch Stabilized Chlorine Tablets

For most swimming pools and weather conditions, you only need one to two of these chlorine tablets per week for every 10,000 gallons of pool water. The tablets are thick and dissolve slowly to protect pool water longer.

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BioGuard Silk Guard Complete 3-inch Chlorine Tablets

Besides cleaning the pool water of bacteria, these tablets provide stain control, prevent limescale buildup and prevent algae. They also prevent staining on metal components in the pool, such as ladders.

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Rx Clear 3-inch Chlorine Tablets

These tablets have 90% available chlorine, meaning they’re 90% as strong and effective at killing bacteria as chlorine gas. Simply add two tablets per 10,000 gallons of water to a floater or chlorinator to slowly distribute throughout your pool water.

Sold by Amazon

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Lauren Farrell  writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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