Nuke bacteria and algae and keep your pool clean and sparkling with the best chlorine tablets for swimming pools. Let’s do this.
There’s a lot of fun and enjoyment to be had with your swimming pool.
It’s tough to beat those long summer days, feet dangling in the cool water with family and friends.
Of course, along with the fun and good times that come with your swimming pool is the frequent cleaning and maintenance required.
Whether it’s attending to your pool vacuum, using a robot pool cleaner to automate cleaning, or collecting leaves with a pool skimmer, keeping the pool water clear and clean can feel like a full-time job.
Chlorine tablets are a way to keep your water sparkling clean, avoiding obnoxious algae blooms and restricting yucky bacterial strains from infecting people swimming in the water. Although chlorine is an assassin when it comes to bacteria and even insects, it’s safe for humans when kept at appropriate levels (1 to 3ppm) and the pool water is probably balanced.
📣 Fun fact: While other pool disinfectants exist, including bromine and iodine, chlorine is by far the most effective at killing bacteria like E. coli and strep.
Chlorine tablets are great as they dissolve slowly over time, are premeasured (no scooping), and can be added to a floating chlorine dispenser for ease of application.
In this round-up of the best chlorine tablets for backyard pools (and hot tubs), we are going to take a deeper look at the best-reviewed tablets on the market.
Read on, find the best chlorine tablets for your pool, and get back to enjoying the cool, clear water.
Clorox Pool & Spa Active Chlorinating Tablets
Clorox is synonymous with cleaning products, and this bucket of chlorine tablets (35 pounds worth!) contains enough three-inch tablets to keep your pool sparkling and shiny all summer long.
An individual tablet will disinfect a 5,000-gallon body of water and slowly melt into your pool water over time (average dissolve time is about 4 to 5 days). Clorox’s chlorine tablets are individually wrapped to help protect your fingers and skin from burning.
📣 Fun fact: Chlorine tablets come in stabilized and unstabilized forms. If your pool is outdoors, use the stabilized tablets.
The trichlor tables also include a stabilizing agent that helps reduce the UV breakdown of chlorine, making it especially ideal for outdoor pools. Clorox also has a free app that you can use in conjunction with these tablets to properly assess your pool acidity and cleanliness.
Rx Clear Chlorine Tablets
The Rx Clear Chlorine Tablets get high marks for affordability and effectiveness. While the tablets are smaller (1”), and correspondingly will have to load up your skimmer or dispenser with more of them, these stabilized chlorine tablets get the job done.
Recommended dosage is 6-7 tablets per 2,500 of water, with each dose lasting up to a full week of clean, cool swimming fun. Rx Clear notes that sometimes tablets will break over the course of shipping, but that this doesn’t reduce the potency of the tablets.
📣 Fun fact: Most chlorine tablets used for private swimming pools are actually sodium hypochlorite, a mix of chlorine and sodium hydroxide.
These tablets get crazy-good reviews on Amazon, with over 1,500 five-star ratings, with owners of both pool and hot tubs noting how fast they clean and how long they last.
HTH Super Chlorinating Tablets
The HTH Super Chlorinating Tablets are another large tablet, at three inches. The obvious upside to this is that a 10,000-gallon pool only requires one tablet per week.
Made with cyanuric acid, these tablets dissolve slowly and prevent chlorine loss while also donkey-punching algae and bacteria. HTH markets this as part of their “pool protection” portfolio which includes an algae-specific protector, shock, and a pool test strip kit.
📣 More fun facts: The “smell” of chlorine in swimming pools isn’t from chlorine, but a byproduct called chloramines that occur when chlorine mixes organic substances like sweat, pee, etc.
The 8lb container pictured below will contain around 16 tablets in it, giving you a solid four months of clean pool water (depending on pool size, obviously) and retails for around $60 per 8lb container (check Amazon for current pricing and availability).
Clorox Small Pool & Spa Active Chlorinating Tablets
The chlorine tablets reviewed so far are generally designed for larger swimming pools. The Clorox Small Pool Chlorinating Tablets—as you can probably surmise from the name—are designed with smaller pools and hot tubs in mind.
Ideal for inflatable backyard pools, the 1” chlorine tablets are formulated with stabilizing agents to reduce chlorine loss.
Algae and bacteria in pools up to 5,000 gallons won’t know what hit them when you drop these bad boys into action. Available at Amazon—check for current pricing and shipping options.
In the Swim 3-Inch Pool Chlorinating Tablets
In the Swim is a player in the pool cleaning and equipment market—I’ve previously reviewed their above-ground swimming pool covers and found them to be better than average.
These tablets are large and designed for larger swimming pools, with each tablet weighing in at 7oz and three inches in length.
The In the Swim Chlorinating Tablets come in the largest size in the market, each bucket 50lb and containing approximately 114 tabs.
If you have a larger pool, or multiple pools, or simply don’t fancy going to the pool shop over and over again for chlorine tablets, this bucket has your name all over it.
Chlorine Tablets – FAQ
Got questions about chlorinated tablets?
I’ve got some answers to your chlorine inquisitions below!
What’s the best way to add chlorine tablets to my pool?
While you might be used to the old-school method of scooping chlorine granules into the pool (my local lap swimming pools still do it this way when there is an “accident” in the water), we don’t need to go that route with tablets.
There are a few different ways to add chlorine tablets to the pool that allow for a delayed release that will keep the water clean over time.
Floating chlorine dispenser.
Most frequently used in hot tubs and smaller pools, these little floating islands slowly bob around your pool, steadily dissolving the tablets inside them.
They are inexpensive and really easy to use, but for softer pool walls like vinyl not always the best choice.
The main downside of pool chemical dispensers is that they frequently get stuck behind pool ladders or bobbing up against a pool floatie, dispensing too much chlorine in one spot and potentially damaging the pool liner.
Pool skimmer basket.
A more automatic solution that will also more thoroughly distribute the water-cleaning chemical is to drop the tablets into your pool skimmer bucket.
The pump pushes water through the bucket, taking with it small granules of chlorine and spreading that cleaning goodness across the full area of your swimming pool.
As with just about everything in the pool (and life), there is a downside.
When the pool pump is not running, the tablets sit there, slowly dissolving and potentially ruining your skimmer bucket with highly concentrated chlorine.
Workarounds include being Johnny-on-the-spot with removing partially dissolved tablets or using a variable speed pump, one of my all-time favorite tools for its ability to run at lower speeds, continuously moving water while also reducing hefty energy bills.
A more heavy-duty approach for maximum convenience (along with a higher price tag compared to a plastic and floating dispenser) is using an automatic pool chlorinator.
These devices take out a lot of the guesswork and hands-on work that comes with using chlorine tablets.
Load up the chlorinator, set it to a preferred level of chlorine, and it will disperse the right amount of chlorine. These tools generally work with both small and large tablets, and they are easy to adjust with a dial control valve.
Hayward and other leading brands make automatic chlorinators for about $40-100, so if you want to make sure that your tablets are doing their job perfectly every time, they are worth a look.
What are the different kinds of chlorine tablets?
These bad boys come in two different sizes: one-inch and three-inch tablets.
Which one you choose is ultimately up to you, but the three-inch tablets are #1 in our hearts because they are usually less expensive because you end up using fewer of them to clean your swim pool.
In personal experience, the larger tablets are also easier to handle and add to the pool. And if you are the kind that frequently forgets to do the routine cleaning and maintenance checklist for your pool, a larger tablet is more ideal.
How many chlorine tablets per week?
Trying to decide how many chlorine tablets to your pool is actually quite straightforward.
Generally, 2” and 3” tablets are one per week, per 5,000 gallons.
For example, a 10,000-gallon pool would get two tablets per week.
Where things get tricky is when swim pools have a volume that lands between the 5,000s.
An 8,000 or 12,000-gallon pool for example.
In each case, round up.
- 8,000 gallon-pool = Two tablets per week.
- 12,000-gallon pool = Three tablets per week.
Of course, double-check with the manufacturer of the tablets you end up choosing for your swim pool.
What’s the best way to store chlorine tablets?
Pop quiz: what doesn’t take a holiday?
Chlorine tablets, like Tide pods, are not snacks and accordingly should not be ingested. Seems like a super obvious thing to say, but in this day and age, disclaimers are first and foremost.
Pool chemicals should always be stored properly and away from the curious hands of children.
Now, let’s move on in terms of how to store chlorine tablets to make them last longer.
Chlorine tablets have a pretty good shelf life, typically lasting around 3-5 years when properly stored. While they are usually wrapped in plastic to give them a little extra longevity, they still do degrade.
The main things to remember with chlorine tablets is to store them out of the reach of kids and to also store them at the right temperature, which is in the neighborhood of 50-70 degrees Fahrenheit (or 10-21 degrees Celsius).
Chlorine tablets are shipped in buckets that feature a tight seal, and when closed properly, will seal that pool-cleaning goodness for years to come.
Heat causes them to degrade, so if you live in a particularly warm climate, consider putting them up on a shelf in your basement where there is some ventilation.
And remember to always keep it out of direct sunlight.
What can I use instead of chlorine tablets?
Like many household items during the Covid pandemic (end date apparently TBD), chlorine tablets became difficult to find in some parts of North America.
Part of the increased demand is due to people simply building more new pools and domestic manufacturing taking a hit due to extreme weather.
The Bio-Lab facility in Louisiana, which produces most of the chlorine tablets in the US, had a big fire following Hurricane Laura in 2020, leading to shortages across the United States.
So, whether you are temporarily out of stock or you want to try something different, there are some alternatives to chlorine tablets out there, including changing your pool to saltwater or ozone system, or for indoor pools and spas, bromine.
But when it comes to a short-term solution for keeping your pool clean, your best bet is liquid chlorine.
Easy to apply (what’s easier than dumping liquid into a pool?), liquid chlorine has a lot of the same cleaning power of tablets. It also doesn’t require a dissolving period since it’s already a liquid.
The only problem is that because liquid chlorine is only about 10 to 12% chlorine, you will need a significant amount of it to create the same cleaning power as concentrated tablets.
Additionally, liquid chlorine does not last very long, with a big bottle of it degrading within weeks, its potency quickly draining.
That said, if you are in limbo between waiting for tablets to come back in stock or arrive in the mail, liquid chlorine is far and away your best option for keeping your pool clean and clear.
How long do chlorine tablets last?
Stored properly, chlorine tablets will last 3-5 years.
They can retain up to 98% of their chlorine content after three years1.
More Pool Cleaning and Maintenance Guides
6 Best Pool Brushes for Deep Cleaning and Tough Stains. Keep your swim pool and/or hot tub in sparkling condition with our collection of the best pool brushes for algae and assorted pool gunk.
6 Best Pool Skimmers for Above Ground Swim Pools. Keep your backyard swimming pool nice and clean with our hand-picked skimmers for above ground swimming pools.