How to Shock Your Hot Tub Fast—And Why You Should

Chances are you know the story. Maybe you’re on vacation with your family at a hotel, or you’re visiting a friend—and you’re excited to know there’s a hot tub on the property. But the closer you get, the more you cautiously sniff the air. Maybe you were even impressed by how seriously the spa waters were maintained. Because that smell had to be chemicals. Right?

Actually, wrong. That strong, chemical-like smell is actually a red flag. It indicates that the hot tub lacks proper sanitation, and could potentially host unwanted bacteria as a result—including the type that can make you sick. What’s more? This smell is more or less guaranteed to happen if you don’t use spa shock. I’ll explain why this is, what spa shock does, and how to use it in a way that you can be sure it works—and get back to a long, safe soak in no time.

What is Spa Shock? Sounds Fun!

You might already know what pool shock is, and how to use it. That’s great—shock is super important to use in pools, too. But whatever you do, don’t overlook spa shock. Essentially, it’s an intense dose of oxidation. And unlike your basic chlorine, it enacts a more specific function than simply sanitizing your pool water—though it does that, too.

Here are the facts: after a chlorine or bromine particle attacks and kills bacteria or another organic material in your hot tub, it creates what is called a chloramine or bromamine. This is an inactive particle that floats along in your water until it can be broken apart. That’s when spa shock comes in: to finish the job.

I Already Sanitize. Why Do I Also Need to Shock My Hot Tub?

There’s probably a reason you have a hot tub: you love a good, warm soak. Unfortunately, bacteria also share this pastime. If you don’t have enough disinfecting chemicals circulating throughout your water (or, too-low circulation), the germs which might make you sick could thrive. You might think the answer to this is to sanitize your hot tub with chlorine or bromine. That’s important to do, but it’s alone not enough.

Chloramines and bromamines prevent how well all sanitizing chemicals work moving forward. This is because they take up space, greatly reducing the free chlorine or bromine in your hot tub. Without spa shock, they will continue to reduce your sanitizing ability until your hot tub looks more like a hot pond.

As with any sanitizing chemicals, circulation is key. Make the best long term decision with the 1.5 HP Variable Speed Blue Torrent Thunder Pool Pump. It pays itself off in under a year with energy saved, is eligible for rebates, and comes with a lifetime warranty. That’s a no-brainer.

Step Aside, Kale. Contaminants Can Be Organic, Too.

That sunscreen you put on two hours ago, the shampoo you used last night, the skin cells your body no longer needs. Much of the miniscule stuff that your body came into contact with throughout the day comes off into the spa water. If you’re soaking with others on a regular basis, well—I think we can all agree we’re about pools and hot tubs, not cesspools and hotter cesspools.

how to shock your hot tub

Let’s Face It. Chloramines Stink!

There’s no way around it: chloramines smell bad, and they’re a sure indicator that your water is contaminated. And now that you know that, there’s no going back to soaking in a malodorous spa. Yuck.

It’s Simple: No Shock, No Sanitizing.

Without free chlorine or bromine, all the bacteria that prevents your hot tub from being clean and safe—some bacteria are pathogenic, after all—will continue to happily live on. Basically, that pool pump you run for the proper amount of time every day, the pipes that connect it to your pool, the sanitizing chemicals you add... all of these actions which take time and money to keep your hot tub in shape are compromised.

It’s important to keep your hot tub covered when you’re not using it—but what if your cover isn’t quite holding up in the storm? Keep it dry and secure with the Sunnora 350 GPH Automatic Cover Pump. According to customer Richard Hogan, “works great.”

Okay, I’m All About Spa Shock Now. But How Do I Choose?

We agree that chloramines and their slightly less noxious counterpart, bromamines, aren’t welcome here—and you’ll probably be tempted to reach for the most popular pool shock to get rid of them. But hang on: calcium hypochlorite is not for you. This is because it’s intended only for pools: it’s unstabilized, meaning that it breaks down in heat like direct sunlight—and loses 95% of its effectiveness in a hot tub.

There are many types of shock on the market, and sometimes it can feel overwhelming to choose. So I’ll just tell you now: to shock your hot tub, you’ll want to use a stabilized shock like dichlor shock, which is also inexpensive and widely available. That is, unless you use two specific sanitizers: for a biguanide sanitizer, you’re better going for a biguanide shock, and for a spa mineral sanitizer, you’ll want non-chlorine shock. Easy, right?

how to shock your hot tub

Got My Shock. How Much Do I Use?

Like all quality swimsuits, spa shock is not one size fits all. You’ll want to look at the label of your shock to follow the recommendations of your manufacturer, which will be based on the size of your hot tub.

Not sure how many gallons your hot tub holds? It’s simple math—and I mean simple. You just have to multiply the length, width, and depth of your spa in feet, and then multiply that figure by 7.5 to convert the number to gallons. If you think better with formulas, follow the one below:

[Hot Tub Length in Feet] x [Hot Tub Width in Feet] x [Hot Tub Depth in Feet] x 7.5 = [Volume of Your Hot Tub in Gallons]

Keep your greater circulation system in top shape with the 1.5 HP Variable Speed Blue Torrent Thunder Pump. This robust and thorough pump is the most reasonable decision any pool owner can make: comes with a lifetime warranty, is eligible for rebates, and pays itself off in under one year.

How to Add Spa Shock

To properly add spa shock, just follow the steps below. And remember: safety gloves and goggles are recommended. Spa shock might not be as electrifying as it sounds—but it’s still a chemical.

  1. Make sure your hot tub is uncovered and any accessories are removed from the water (and people, which goes without saying… right?).
  2. Use test strips to ensure that your spa’s pH level is between 7.4 and 7.6, and adjust your levels as needed.
  3. Turn off the jets, but keep your circulation pump on. This will help the shock distribute evenly across your water.
  4. Measure out the amount of shock you need, according to the manufacturer’s instruction on the label.
  5. Carefully add the shock to your water using the method recommended by the manufacturer—usually this is directly into the water. Done!
  6. Oh, and if you spilled a bit, make sure you clean that up—especially if you have children or pets. You don’t want another type of shock coming your way.

Need better circulation for your above-ground pool system? With different horsepower options, the Copper Force Pool Pump runs cool, quiet, and includes a start capacitor to eliminate failure-prone mechanics found in other above-ground pumps. As customer Edwin Feliu says, “so quiet you don’t even know it’s running.”

Done Shocking. How Often Do I Need to Repeat?

Throughout the season, I recommend you use spa shock once a week—at the least. If your hot tub is in use frequently, or by many people, you should do up to twice weekly. Seems like a lot? Don’t sweat it—if you add it to your routine of basic pool maintenance, you’ll hit a flow comparable to the chemical circulation of your dreams.

Trust me: your skin and your nose will thank you.

how to shock your hot tub

You Went Ahead and Shocked. Now You Can Soak.

Once your sanitizing levels are back on track, the spa is once again yours for the taking—and you’re more than ready to dip into its warm, odorless waters. Ahhh. That’s what all the hard work is for: an even greater payoff. And what makes this even better? Not only have you kept irritants at bay, but you can be sure the water is safe. All the more reason to enjoy. Take it easy.


Related articles:

Sand in Your Pool? Here’s Why—And How to Fix It

Chlorinate Your Pool in Three Easy Steps

The Safest Way to Store Your Above Ground Pool For Winter

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