Hey, it’s always good to know your options. And I would argue that choosing the right sanitizer is as important as deciding between wood or tile flooring in your kitchen, and leather or fabric-covered seats in your car. Sanitizer is an essential and unavoidable part of keeping your pool water clean and safe, and not a single swimmable pool doesn’t have it. And after all, this is a chemical you’ll be adding to your pool on a continuous basis.
Although chlorine might be the only recognizable name on this list to a DIY pool maintenance beginner, all other sanitizers are worth knowing about—and each have its own strengths and weaknesses. Here, I’ll explain why sanitizer is important, what makes each sanitizer unique, and how to add each to your pool. This first one is going to be the easiest.
But Why Do I Need a Sanitizer In the First Place?
Left totally unchecked, your pool water will quickly turn into cloudy feeding ground for bacteria and organic contaminants like algae. Other than just being nice to watch, water that’s truly free of dirt and grime is also free of bacteria, including the kind that can make you sick. So yeah, it looks nice to have a clean pool—but it’s actually the only safe way to swim. You can skim and vacuum your pool, have the right pool pump, and run it for the perfect amount of time every day—and you should. But sanitizer is the only thing that will tamp down on that nasty bacteria on a microscopic, continuous level.
So What Does Sanitizer Do?
Get ready for one simple explanation: when added to your pool properly, your sanitizer inactivates the bacteria in your water. This doesn’t mean that the bacteria is technically completely removed—you’ll need the right pool filter and the help of pool shock for that—but the bacteria will no longer be able to make you sick. Who wouldn’t be all for that?
Why Does the Kind of Sanitizer Matter?
Just like with virtually any other choice we make, sanitizers have their pros and cons. They not only vary in how much they cost and how much work it takes to get them properly circulated in your pool, but they also can be the deciding factor for the comfort of the swimmer.
Chlorine and bromine are notorious for being uncomfortable to those who are a little more sensitive. But if you do opt for another sanitizer, don’t think you’re done! As you’ll see, some of these sanitizers are not meant to be used on their own, but can reduce the amount of chlorine or bromine you use. Sorry, that’s just how it is right now.
Keeping your sanitizer effective is all the easier with a powerful pump. If a larger horsepower will turn over your water volume at a sufficient rate—and won’t overwhelm your filtration system—then a unit like this Blue Torrent 2 HP Variable-Speed Pump is the one to try. As customer Dave Schmidt says, “My pool has never looked cleaner. I am pleased with my new pump!”
Find Your Match: Which Sanitizer is Right For You?
Now that you’re got the right mindset, let’s dive right in. I’ll explain what makes each sanitizer stand out, as well as the strengths and weaknesses of each. And to start, we’ll cover the one and only classic.
1. The Popularity Contest Winner: Chlorine
You probably know this one. But did you know that chlorine is the most common, and the most inexpensive sanitizer on the market? It’s also unmatched in effectiveness except for it’s more expensive cousin bromine, which we’ll get to next.
Generally considered the standard sanitizer, chlorine is widely available, and will keep your weekly operating costs fairly low. Plus, it comes in many different forms—from liquid, to granules, to tablets—and can be added in a few different ways. This one earns the versatility award for sure.
As I mentioned, chlorine is notoriously irritating to sensitive swimmers. It can sting eyes, noses, throats, and even turn blond hair green. If this is you or another frequent swimmer, you could always convert your pool with a saltwater generator like the Salt Ways Eco Friendly Salt Chlorine Generator, which works great and comes with a lifetime warranty. Although saltwater pools do use chlorine, they keep chlorine levels so low and stable, you’ll hardly know it’s there.
Another drawback to chlorine is the inactivated contaminants that it leaves behind, which are called chloramines. These particles no longer have the ability to make you sick, but they are ridiculously irritating to eyes, noses, and throats—even for people without sensitivities. These chloramines are exactly the reason why you need to shock your pool every week.
2. The Runner Up: Bromine
It’s no surprise that bromine and chlorine sound so similar—they’re practically related. But because it’s nearly odorless, bromine is more popular in indoor swimming pools. Plus, it’s the go-to hot tub sanitizer, because unlike some forms of chlorine, it’s super stable in warmer temperatures. So why don’t people use bromine more than chlorine? Well, that one’s easy: it’s just more expensive.
Unlike chlorine, which inactivates itself after neutralizing bacteria and other contaminants, some parts of bromine keep working (and are even activated by pool shock!). So not only does it have less of a smell and works better in hotter temperatures, but you actually need less of it to sanitize your pool. That’s a major win—but still doesn’t make it as affordable as chlorine.
Other than the high cost of bromine, there are a few other cons—those they’re pretty minor. Although bromine has less of an odor than chlorine, it’s harder to wash off after a swim or soak. Plus, if you or yours have a chlorine sensitivity, a switch to bromine won’t do: it’s based with the same chemical, and will probably incite the same reaction.
Oh, and those nasty chloramines? You won’t technically get them with bromine, but you’ll get their super similar fraternal twin: bromamine. I know, it’s really too bad.
The Higher-Maintenance Loophole: Biguanide
Polyhexamethylene biguanide (say that five times fast) was originally developed in the late seventies as a pre-surgery, anti-microbial scrub. Now, it has the only EPA approval as the non-chlorine sanitizer for pools and spas. It’s also peroxide based—in the same chemical family of the liquid you’d use for an ear infection. Sounds great? It mostly is, but fair warning: this one will take some time and money to keep maintained.
Biguanide is the only—yes, only—sanitizer that can be used without the help of chlorine or bromine. If you have a serious chlorine allergy, this one is the way to go—and one that is actually chloramine-free, odorless, and fairly stable. Plus, biguanides are often combined with algaecides. If you have a recurring algae problem, that’s one unbalanced bird, two chemical stones.
You might need to switch your pool filter for this one. Diatomaceous earth (DE) or cartridge filters aren’t typically recommended by biguanide manufacturers, so you’ll want to opt in for the classic sand filter, though it’s recommended you replace your sand media every two years. Plus, test strips for biguanide aren’t considered to be consistently accurate.
It might also cloud up your water, and its sanitizing effects might diminish over time. Plus, all those other contaminants: like sweat, body oil, and the other stuff we won’t talk about? Biguanide alone won’t do anything to get rid of them. You’ll need to use an oxidizer specifically made for biguanide pools, which is yet another expense.
Biguanide sanitizers are also incompatible with ozone, detergents, ionizers, and other common chemicals. And adding chlorine? Typically, that’ll turn your pool bright orange. This isn’t that kind of science lesson!
Here because your current sanitizer isn’t cutting it? The problem might be bad circulation due to a weak pump. Try a booster pump like the dual-voltage Universal Booster Pump to increase performance. According to customer Jerad Wilson, “Great pump, quick delivery, and great pricing. Would buy from here again.”
The More Complicated Combo: Mineral System
Pool minerals use silver and copper to prevent bacteria and algae from setting up shop in your pool. I know what you’re thinking: isn’t metal the last thing we want in our pool, especially those who struggle with pesky metal stains? Well, not exactly. Silver has antibacterial properties and copper is often used as an algaecide.
Mineral System Pros
In addition to silver and copper, mineral systems can also include zinc for its antibacterial properties, and limestone to absorb chlorine acid and maintain your water’s pH. Plus, they keep your water softer, keep chloramines or bromamines low, and reduce wear on your greater circulation system. Sound great, right? Well, keep reading.
Mineral System Cons
Sorry, but you’re not actually avoiding the two common sanitizers here—this mineral system alone won’t do the trick. It needs to be supplemented with chlorine or bromine, though you will need less. And buying two chemicals (minerals and chlorine, or minerals and bromine) will cost. Plus, you might have to deal with some serious oxidized metal stains, which aren’t as easy as you’d think to remove. Sometimes you even have to drain your pool partway—and anyone who has done that knows it’s best avoided unless absolutely necessary.
What About Pool Shock?
For chlorine and bromine, you can use the same tried-and-true calcium hypochlorite, also known as pool shock. For a biguanide sanitizer, you’re better opting in for a biguanide shock, and for a spa mineral sanitizer, you’ll want non-chlorine shock.
How to Add Sanitizer to Your Pool—The Right Way
Of course, once you find the right sanitizer for you, you’re going to have to get it in your pool somehow—and then repeat that process over and over again for the rest of your pool-owning days. Here’s generally what you can expect.
Because it comes in so many different forms, the way chlorine can be added to your pool is endless: anywhere from floating chlorinators (which I don’t recommend, since they don’t circulate evenly throughout your water), to adding tablets directly to your pool skimmer, to installing an automatic chlorinator to your greater circulation system. Learn more about how to properly chlorinate your pool to find the method that works for you.
Bromine tablets can be added to your pool exactly the same way as chlorine tablets—just keep in mind that because bromine is stable, it can also take a while to dissolve and circulate throughout your pool.
You’ll want to follow the manufacturer’s instructions for this one, but since biguanides come in liquid form, they can often be added directly to your water. What’s easier than that?
Admittedly not as easy as biguanides, but nothing too complicated here. Mineral sanitizers have dispensers that you can lower right into your pool’s skimmer basket, and last about six months. You can also use a floating dispenser—again, not my favorite—or hook up a mineral feeder to your circulation system plumbing, much like an automatic chlorinator.
Sensitive to chlorine (and by extension, bromine)? Avoid expensive biguanide costs by switching over to saltwater, so that your chlorine is operating at the lowest, safest, and most consistent levels possible—and make a smooth transition with the Salt Ways Eco Friendly Salt Chlorine Generator. It’s ultra-reliable and comes with a lifetime warranty.
Now The Fun Begins!
You know what sanitizer works for your budget, preferences, and schedule, huh? Now put it to the test. Remember, you’ll be sanitizing frequently from now until forever, so it’s always good to find the chemical deserving of your confidence. Integrate it into that DIY pool maintenance routine, and you’ll have all the more time to enjoy your cool, clean pool. Enjoy.