Pool owners know that having a pool gets expensive quickly, especially when it comes to purchasing the chemicals that keep your backyard oasis sparkly and sanitary.
One way people like to save is by buying pool chemicals in bulk. But do they have a shelf life? How many seasons can you use your pool chemicals?
The answer is that it depends on the chemical. Some have a long shelf life, while others lose their effectiveness reasonably quickly—and these are the chemicals you should purchase as needed.
Today, we’re going to look at the expiration date of common pool chemicals. We’ll also go over how to store and dispose of them properly.
|Primary Pool Chemicals||Average Shelf Life|
|Granular Chlorine||5 Years|
|Liquid Chlorine||6 Months|
|pH Increaser & pH Decreaser||5 Years|
|Tablet Chlorine||5 Years|
|Test Strips||1 to 2 Seasons|
|Alkalinity and Calcium Increaser||5 Years|
|Pool Clarifiers||5 Years|
|Stain and Scale||5 Years|
First things first: all pool chemicals have a shelf life, which can vary considerably from one to another.
If you want to keep your pool sanitized and beautiful, it’s vital to keep expiration dates in mind, especially when it’s time to store the chemicals at the end of the pool season. You don’t want to become that pool owner with tons of leftover expired pool chemicals every year.
To keep you on track, here’s how long you can expect the most commonly used pool chemicals to last.
Of the three forms of chlorine, liquid chlorine is the most unstable form. So you can expect it to lose quite a bit of potency in the first year—about half in the first six months and around ninety percent after a year.
Because it’s so unstable, storing it incorrectly makes it lose potency even faster. Direct sunlight and extreme temperatures are the enemies of liquid chlorine.
Granular chlorine (or pool shock as it’s also called) has a longer shelf life. When stored properly, you can expect it to last about five years. Otherwise, it’s not uncommon for this chemical to become ineffective after a year or two.
If you’re looking for the most extended shelf life. After three years of being stored at the proper temperatures, its effectiveness is hardly unchanged. In most cases, it’s good for up to five years.
Test strips are another pool maintenance item that you should keep an eye on. They typically have a short shelf life, and once expired, the test strips may be inaccurate.
You can expect them to last anywhere from a season to two, but always be sure to check the expiration date at the start of the summer.
If you want to keep your pool water balance in check, you need strips that give you an accurate reading. Otherwise, it’s easy for your pool chemistry to be compromised and problems to occur.
When it comes to pH increaser and pH decreaser, both can have a long shelf life. You can expect them to last around five years or more.
In the case of pH increaser, you’re likely to get more than five years of effective use. So this product is one you won’t have to worry about each season.
However, pH decreaser presents an interesting concern. Because they’re acids, they need a strong container for storage.
If the plastic packaging is too thin, it can become compromised after prolonged contact with acids. For this reason, it’s best not to let them sit for the full five years. Instead, try and use them up.
Several other chemicals last quite a long time as well. These include:
In general, you can expect the above chemicals to last about five years.
A big mistake pool owners make is not storing their pool chemicals correctly. Leaving them in the wrong conditions is a surefire way to lessen chemical effectiveness—or even create unsafe situations.
Here are some tips to keep in mind.
Pool chemicals are far from cheap, so it’s normal to wonder if they’ll still work past their expiration date.
The answer? In most cases, the chemicals will probably still work. However, they’ll be slightly less effective than when you first bought them. The decision is yours to make, but definitely avoid using old chemicals if they smell bad, have changed color, or have separated.
If you find yourself with unused, expired pool chemicals, it’s critical to dispose of them properly. You should treat them like you would any other hazardous household waste. Never put the chemicals in the trash, down the storm drain, or into a home drain. Instead, the friendly folks at your nearest hazardous household waste center know how to dispose of them.