Automatic Pool Chlorinators: The Easy Guide

Michael Keenan


Pool Water Chemistry

If you go on vacation or you’re away from your swimming pool for a few days, you shouldn’t have to worry about the chlorine level in your water and the possibility that the pool will be an absolute mess when you return.

Although making sure your pool has enough chlorine is a chore you’ve become accustomed to, the task can be made much easier once you get an automatic chlorinator, because it does most of the work for you so that you can concentrate on other things.

pool chlorinators

What Is an Automatic Chlorinator?

An automatic pool chlorinator is a piece of equipment you keep in your swimming pool, and it periodically releases the right amount of chlorine into your pool so that you don’t have to do it yourself every time.

Usually, it releases chlorine in the form of liquid chlorine or granules, and it releases the chlorine on a regular basis so that the level is always just right.

Pool chlorinators can be huge time-savers because even though you do have to make sure they have enough chlorine themselves, you’re not doing that nearly as often as you would be adding chlorine to the water yourself.

In other words, they save you a lot of time and stress because chlorine will be released into the water regularly and at the right amounts for as long as it is full, which means you can concentrate on other things for a time.

It should also be noted that an automatic pool chlorinator is not the same thing as a salt chlorine generator as used in saltwater pool systems. Saltwater chlorinators actually create chlorine from salt and manage the levels to sanitize the pool.

In addition, you have to make sure the automatic chlorinator you purchase is appropriate for the type of swimming pool you have, because they are usually made either for above-ground or inground pools, and sometimes both. You should always check this to make sure you get the right one in the end.

Chlorine or any other type of pool sanitizer is only one part of the pool chemical puzzle. Have a good look around this site to learn more about pool chemistry and how the different elements work together to keep your pool water in top condition.

Have you read about using pool stabilizer – cyanuric acid? Find out what role it plays in keeping your chlorine active. Maybe you are wondering why sodium bisulfate is used in swimming pools – I have that covered too.

What Types of Automatic Chlorinators Are There?

There are many types of automatic pool chlorinators on the market, and each of them works a different way. Here is a description of how each one of them works:

Floating Pool Chlorinator

Also known as floating chlorine dispensers these are the cheapest and most basic types of automatic chlorinator. They are also the most popular – probably because they are so cheap and easy to use.

They are useful as an aid to keep your chlorine levels in the right range but they are much more hands on than the other auto chlorinators described below. With the floating dispensers you’ll need to keep a much closer eye on the chlorine levels in your pool.

I see them as a standard way to slow release chlorine into the pool – used as a supplement to my weekly testing and topping up the chlorine levels in my pool.

Aquabeacon Pool Large Chlorine Floater for 3 inch Chlorine Tablets
Holds up to 5 chlorine tablets (3-inch size). Dispenser measures 7.2 x 7.2 x 7.0 inches.

Inline Pool Chlorinator

This type of chlorinator is attached directly to the filtration system in your pool and is usually attached at the end of it right before the water is returned to the pool.

It also helps protect your pool equipment from becoming corroded since the water exiting the pool and entering the filter usually isn’t as chlorinated as the water entering the pool.

Offline Pool Chlorinator

This is the type of chlorinator you’ll need if you don’t have any room to add your chlorinator at the end of your filtration system. If you have some space beside the system, however, you can use an offline pool chlorinator.

This type of chlorinator is attached directly to the filtration system itself, which means you’ll bypass the rest of the equipment.

Just keep in mind that automatic pool chlorinators are specifically made for either offline or inline setups, so you’ll have to check your filtration system to make sure you purchase the right type of chlorinator for your swimming pool.

Setting up the Automatic Pool Chlorinator

The first step in setting up your automatic chlorinator is knowing the amount of water your pool can hold. This is important because some chlorinators are made to accommodate up to 10,000 gallons of water, whereas others can easily accommodate up to 40,000 gallons.

If you aren’t sure how much water your pool holds, there are online pool calculators you can use to find out an estimate. Once you know that number, all you have to do is follow the instructions left by the chlorinator’s manufacturer, and you should be set to go.

Speaking of the online calculators, they break the pools down by size and type then give you a number that should correspond to the number of gallons in the pool. With these charts, the numbers are broken down by above ground and inground pools, pool shapes and sizes, and different wall heights with the above ground pools.

You simply look up which type of pool you have, and you can instantly get an estimate on the number of gallons you likely have in your swimming pool.

Adding Chlorine to the Automatic Chlorinator

As far as the chlorine itself that goes inside of your automatic chlorinator, there are three main types you can use: liquid, granules, or tablets. Any of these will work fine and do the job it was meant to do, but tablets tend to last longer than the other two types, which is why so many pool owners choose that particular kind.

By using tablets, you’ll enjoy longer periods of time between refills, which is especially useful if you’re planning to go on a week-long vacation.

Some automatic chlorinators that use tablets are a little more time-consuming and costly to set up in the beginning as compared to the ones that use either granules or liquid chlorine, but you have to remember that you will have more time between refills, which saves you a lot of time in the long run.

Regardless of the type of automatic pool chlorinator you end up choosing, it will result in less maintenance time overall because the pool will always have the right amount of chlorine in it and therefore the balance of the chemicals you need should be just right.


You already know your swimming pool needs chlorine on a regular basis, and installing an automatic pool chlorinator will allow you to enjoy more free time since it does the job of chlorinating the pool so that you don’t have to do it yourself.

Although some are costly to install initially, they’ll end up saving you both time and money in the long run, which means you can enjoy your swimming pool a lot more often. The devices are convenient and operate on a consistent basis so that you can have the peace of mind you need and deserve 24 hours a day, seven days a week.

Automatic chlorinators are definitely worth every penny, so this is one decision that will make your life easier all the way around.

Last update on 2024-04-14 / Affiliate links / Images from Amazon Product Advertising API

michael keenan author

Author - Michael Keenan

I'm Michael Keenan the owner and creator of the Outdoor Care Guide. I'm a trained horticulturist with over 30 years of experience in pool care, plant care, and landscape care! Seemed like a good idea to share - I think I can make your life easier and save you some time and money!