Chlorine is the most widely used chemical for maintaining the swimming pool. It’s used by pool owners around the world thanks to its great disinfecting power together and its low cost.
We have compiled all the interesting information about the types of chlorine for swimming pools that exist on the market and their functions in the water.
But, for those asking what is the best chlorine tablets on the market, we’ll first review the 10 best chlorine tablets for use in the swimming pool and then finish up with a buying guide and some frequently asked questions. Keep reading!
How to use chlorine tablets for pool?
The first step to using chlorine tablets is to prepare the pool. For a correct functioning of the chlorine tablets, you must ensure chemical balance by regulating the pH level in the water so that it does not get too acidic or alkaline.
The right pool pH levels should be between 7.2 and 7.6. This is important so that the chlorine does its job and does not cause “red eyes” or skin irritation for swimmers.
You should disinfect the pool with up to 2 chlorine tablets of 3-inch size once every 7 days for every 20,000 gallons of water or one 3-inch tablet for every 10,000 gallons of pool water.
Simply add chlorine tablets to your floating dispenser and throw them in the pool.
Our Top 3 Recommendations
Overall Best Chlorine Tablets – Clorox Pool&Spa Active99 3-inch Chlorinating Tablets
Best Chlorine Tablets for Swimming Pool: Our Top 10 Picks
Ready to chlorinate or shock your pool? Here we’ve reviewed the 10 best chlorine tablets for pools. But first, check out our three top recommendations
1. Clorox Pool & Spa Active99 3-inch Chlorinating Tablets – Overall Best Pool Chlorine Tablets
The Clorox pool and spa chlorine pills are the overall best pool chlorinating pills in this review because they have a 2-in-1 formula that gives you a huge advantage in maintaining your pool. The formulation essentially controls algae growth and kills bacteria. It removes organic contaminants for better water.
But to get the best results, it’s essential to check and balance the water before application, which means you should use a test kit to assess chlorine level, pH level, alkalinity, and other water quality assessments.
Each of these pills is 3 inches wide and durable, meaning your swimming pool water will be healthier for longer, despite sun exposure. However, the chlorine tablets are not separately packaged, which makes managing them somewhat difficult and dangerous.
- UV stabilized tablets
- Controls algae growth
- Kills bacteria
- Pills are not wrapped individually
2. In The Swim 3″ Stabilized Chlorine Tablets for Sanitizing Swimming Pools – Runner Up
The In The Swim 3-inch chlorine tablets are individually wrapped and are stabilized. The stabilizer prevents chlorine loss in the water so it keeps the pool sanitized for longer. Its stabilized chlorine tablets are slow dissolving and include 90% available chlorine.
The chlorine content is Trichloro-S-Triazinetrione (tricolor) and each chlorine tablet is 8 ounces or 225 grams. All the chlorine tablets are in an easy-to-open bag but they are individually wrapped.
Three inches in size, the chlorine tablets are made to fit the automatic chlorinator perfectly. The suggested dose is 1 chlorine tablet per 10,000 gallons of water. But don’t forget to test the water to know the chlorine levels at least once a week.
- Eliminates bacteria and algae
- Slow dissolving chlorine tablets
- Compatible for saltwater pools
- Cannot soften or smoothen pool water
3. HTH 42043 3-inch Super Chlorinating Swimming Pool Chlorine Tablets – Best Quality
If you want to treat your pool water in 4 ways, the HTH 42043 is a fantastic choice to consider because the item contains active ingredients that fight algae, sanitize pool water, stop stains, and clarify water.
On the other hand, the pills come in a small 8 pounds bucket. Each 3-inch pill or 7.6 cm tablet has been stabilized with cyanuric acid (CYA) to have an integrated resistance to the sun. This allows the chlorine to survive longer for a week of disinfection.
Regarding the application, the pills can be treated using your pool skimmer, in addition to a float or automatic pool chlorinator.
- Contains algaecide and clarifier
- Stabilized to last longer
- One tablet can treat up to 10,000 gallons of water in a week
- Ideal for pool cleaning
- Crumbles too easily
4. CLOROX Pool & Spa XtraBlue 3-Inch Long Lasting Chlorinating Tablets
The Clorox XtraBlue is a 5-pound bucket of chlorine tablets for your pool that are simple to apply since you can use a float, feeder, or skimmer to dispense them. One dose of a tablet is enough for pools up to 10,000 gallons.
The XtraBlue is a 3-in-1 chlorine tablet product that is formulated to prevent algae growth, kill bacteria, and contain cyanuric acid for sun protection.
Regardless of how large this package is, each has 3-inch pills containing a high concentration of Trichloro-S-Triazinetrione to successfully kill algae and bacteria.
However, for easier handling when applying, each of these pills could have been individually wrapped as chlorine is very toxic, especially when concentrated.
- Easy to use with floats, automatic chlorine feeders, or skimmers
- Available in different container sizes for different pool dimensions
- Large 3-inch chlorine tablets with Trichloro-S-Triazinetrione concentrate
- Not individually wrapped
- Not for hot tubs
5. Rx Clear 1-Inch Slow Dissolving Stabilized Chlorinating Tablets
The RX Clear is a multi-functional chlorine product that acts as a bactericide, disinfectant, and algaecide. The chlorine pills are absolutely like the In The Swim product as they are in individually wrapped pieces which are safer to manage as they will not emit chlorine fumes when stored.
However, they are smaller in size, with each measuring one inch. These chlorine tablets are packaged in an 8-pound bucket and each weighs 0.5 ounces. The dose needed is around 16 ounces chlorine per 10,000 gallons of water per week.
On chemical formulation, the pills contain 99% strong and concentrated trichloro-S-triazinetrione chlorine, which makes them very powerful.
With the chlorine stabilizer in them, the tablets dissolve slowly, even in swimming pools under the UV rays of the sun. This usually means your pool water is protected from germs for longer intervals.
- Individually wrapped pills for safety and convenience
- The pills slowly dissolve
- 99% Concentrated Trichloro-S-triazinetrione
- Contains stabilizer for sun protection
- Chlorine tablet come in small size
6. Ecoone OneShock Self-Dissolving Spa & Swimming Pool Chlorine Tablets
Formulated for shocking and sanitizing the pool, the ecoone chlorine pool tablets are ideal for swimming pools and hot tubs as it’s formulated from sodium dichloro-s-triazinetrione and has 55.5 available chlorine.
The pool chlorine tablets ensure clear and bacteria-free water and can be used either to sanitize or to super chlorinate.
Containing 64 chlorine tablets, the fast self-acting pool chlorine does what it promises. To use this fast-acting chlorine, you only have to follow the manufacturer’s instructions detailed on the package.
- Can be used both in swimming pools and spas
- Dichloro-s-triazinetrione chlorine
- Less harsh on the skin unlike Trichloro-S-Triazinetrione based chlorine
- Contains 64 chlorine tabs
- Can shock and sanitize a pool water
- No downside discovered
7. GLB 71250A Small 1-Inch Sanitizing Chlorine Tablets
If you want affordability, the GLB 71250A is a good choice. However, this does not indicate that it is a poor-quality item. Its low cost is mainly due to its size, where it comes in a tiny 2-pound container.
Due to these economical dimensions, these would be the best chlorine pills for above-ground pools which are modest in proportion.
Each pill in the container has a dimension of 1 inch and you may need to use more compared to the larger 3-inch pills of the other pool chlorine tablets we’ve seen.
Regarding application, these small chlorinating tablets can be used in a swimming pool with the skimmer or floating chlorine dispenser, and since each contains a chlorine stabilizer, it works for up to a week while gradually trapping and being quite powerful under direct sunlight.
- EPA registered
- Can be implemented using a skimmer, float, or feeder
- Stabilized and therefore it lasts longer even under UV sunlight
- Delivered in very small quantities
- The pills are not packaged separately
8. Pool Mate 1-1404 Jumbo Chlorine Tabs
If you want to treat your pool water two ways, you need to get the Pool Mate Jumbo Chlorinating tablets for your pool. The formulation contains chlorine which is used to purify the water from organic contaminants such as algae and bacteria.
The pills also act as stabilizers/conditioners, protecting the chlorine from degradation after being subjected to the sun’s UV rays so that it sanitizes for more, reducing chlorine demand.
But you should use a pool test kit to ensure stabilizer is stored at 40-100ppm, chlorine at 2-4ppm, pH at 7.2-7.6ppm, and total alkalinity at 70 -140ppm so the pills provide you with the best results.
Inside each of these containers are 3-inch chlorine tabs which are individually wrapped for safe and effortless handling, and should be implemented at the rate of 1-3 chlorine tabs per 10,000 gallons of water using a float or an automatic chlorinator.
- Treats pool water in two ways (chlorination and stabilization)
- Available in 3 different container sizes
- Comes in large 3-inch pills that dissolve slowly
- Each pill is individually wrapped for safe and effortless handling
- The tablets break easily
Frequently Asked Questions
Are chlorine tablets enough for pool?
If you’re simply looking to sanitize the pool and prevent bacteria and algae from growing inside, chlorine pool tablets are good enough. Meanwhile, if you want to shock or super chlorinate a pool, then you’d need a large amount of fast-dissolving granulated chlorine.
Are chlorine tablets safe for inflatable pools?
It’s unsafe to add chlorine tablets or other harsh chemicals such as chlorine into a soft pool liner such as that of an inflatable pool or kiddie pool as they don’t have the needed protection from these chemicals.
Alternatively, a small amount of bleach added into the water may be enough for small pools. Even in hard surface pools, adding too much chlorine can be damaging to the pool
How many chlorine tablets to add in 10,000 gallons of water?
Generally, one 3-inch or three 1-inch Trichloro-S-Triazinetrione chlorine tab is usually enough for a 10,000-gallon pool up to one week, if the chlorine is stabilized.
What size chlorine tablets for pool?
Chlorine tablets in buckets are most often in 3-inch tablets. These are easier to dose as you need fewer tablets – just one tab for a pool of 10,000 gallons. For small pools, there are also 1-inch chlorine pool tablets in smaller containers.
Will chlorine tablets keep my pool clean?
By adding chlorine tablets into the water, chlorine tabs will raise the chlorine level and keep your pool clean, free of bacteria and algae for a week. Some tabs have a purifying effect in the swimming pool.
Buying Guide – How to Choose the Best Chlorine Tablets for Your Pool
Chlorine in the form of pills or tablets is the most widely used for sanitizing swimming pools today, but you must take into account a series of factors before buying the ones you have seen.
For example, depending on the size of the pool, you will need the chlorine pool tablets to be larger or smaller, or you will also have to differentiate between a periodic chlorine treatment or a shock treatment due to excess dirt in the water.
Next, we will detail some of the most relevant factors to consider before purchasing chlorine pool tablets for water disinfection.
Chlorine tablet types
Chlorine is a chemical product used in swimming pools for water disinfection. It belongs to the halogen family and has the particularity that when it comes into contact with water, it transforms into chloramine and eliminates bacteria, viruses, fungi, and other existing organic matter in the pool water.
Dichloro-s-triazinetrione based chlorine
One of the most commonly sold chlorine types for pool use is the dichloro-s-triazinetrione chlorine. This type isn’t as harsh as the other tricolor chlorine. So, they are less harsher when they come in contact with skin and you can make use of them in swimming pools and spas.
Trichloro-S-Triazinetrione based chlorine
This is a fast-acting type of chlorine. Depending on the available chlorine, it’s harsher and can cause red eyes and other small issues when they come in contact with skin. Trichloro-S-Triazinetrione chlorines are the most commonly sold but cannot be used in the spa or hot tub.
Calcium hypochlorite is used for freshwater swimming pools. The chlorine doesn’t contain a stabilizer but comes in solid or white liquid form containing 65 to 73% chlorine concentration and is mixed with other compatible chemicals.
Not suitable for very calcareous (hard) water, it requires pH correction and scaling control. It is an emergency solution to consider for shock treatments (to catch up with green water), because it is effective and economical.
Lithium Hypochlorite can be used in any type of water, whatever its hardness. It does not contain stabilizer and is compatible with Bromine treatment.
The chlorine action
Most chlorine tablets combine two or more functions in the same product. Apart from carrying out the disinfection of the water from chlorine, some models have flocculating, anti-algae, and stabilizing action on the water to protect it from the action of ultraviolet rays.
The optimal size is three inches but there are products with 1-inch chlorine pool tablets. These sizes are small enough to be placed directly in the pool skimmer or a floating chemical dispenser, and the chlorine tabs dissolve slowly in the water, guaranteeing optimal sanitization.
Stabilized or non-stabilized chlorine?
Stabilized chlorine contains cyanuric acid (CYA) and helps keep chlorine in the pool longer while unstabilized chlorine tablets dissolve faster and the UV rays kill the chlorine power in the water quickly.
So why don’t we just use stabilized chlorine? The answer is simple, non-destabilized chlorine is used for daily and permanent sanitization while non-stabilized chlorine acts more efficiently in pool shock treatments, or to quickly increase doses in the sanitization process.
In the shock chlorine processes, we can find that the chlorine level is high and the water is usually not suitable for bathing, but unstabilized chlorine tablets practically disappear after 24 hours from their application.
In short, the use of chlorine is the best way to sanitize your pool. Chlorine with CYA content remains in the water much longer and is ideal for daily and permanent chlorination.
On the other hand, non-stabilized chlorine is better for shock treatment since it provides a high concentration of chlorine that practically dissipates 24 hours after its addition. However, note that chlorine granules are better for shocking the pool than chlorine tablets.
Chlorine in the form of pills or tablets is the most widely used for disinfecting swimming pools today, but we must take into account a series of factors before selecting the best chlorine tablets for pool. For example, you will need the chlorine pool tablets to be larger or smaller depending on your pool size.