Pool shock is chemicals added to the pool to sanitize the water from microbes and other bacteria. But pool shock and chlorine aren’t the same things even though most pool owners tend to take them as the same.
In this article, we shall be reviewing the differences and similarities between pool shock and chlorine.

Table of Contents
What is the difference between pool shock and chlorine?
Chlorine and pool shock are different. Although they perform almost the same function. Pool shock is quite stronger than chlorine sanitizer. Also, their mode of use is also different.
Both kill microbes and bacteria, but one is more powerful than the other.
Although they possess similar chemicals that encourage sanitization in your pool the liquid, granular, or tablet chlorine is quite different from pool shock and the difference is visible.
Chlorine is slow when it comes to dispersal. Unlike pool shock. pool shock is quick to release into the water for rapid sanitization.
Also, pool shock is usually unstabilized which means you can only shock your pool in the early hours of the morning, or in the evening when the sun has gone down.
While chlorine, on the other hand, has both options. It can either be stabilized or unstabilized. Traditional chlorine helps to prevent microbes and bacteria and sometimes, algae growth. While pool shock, on the other hand, kills new pollutants, kills bacteria, even though it has a shorter lifespan in the pool, unlike chlorine.
In totality, both are meant to be used together. As a matter of fact, one cannot work without the other.
How Much Chlorine Do You Need To Shock a Pool?
For pool shock, you can’t expect to shock your pool with chlorine and expect to get the same result. Your pool has to be shocked first before your traditional chlorine is added to the pool.
This is because traditional chlorine tablets and liquids/granular are great for balancing the chlorine level in the pool. They don’t necessarily eliminate pathogens, bacteria, and algae.
The pool shock does that on behalf of the chlorine. That is why most pool owners inter-change them. Read more
How Do You Know a Good Pool Shock?
A good pool shock isn’t difficult to come by. A good pool shock when added to the pool raises the chlorine level by 5 ppm and keeps on eliminating the presence of bacteria, and chloramines.
Also, if you have any type of algae in your pool, then you should double, or better still triple the normal measurement of pool shock to get these microbes eliminated. And about 1 pound of pool shock can raise the chlorine level to about 7 ppm.
In fact, pool chlorine shock is the higher version of chlorine concentrate.
Are There Different Types of Pool Shock?
Different types of pool shock exist. However, there are about two types of pool shock that exist. There is the chlorinated pool shock and the non-chlorinated pool shock.
The chlorinated shock is granular in appearance. It is also known as a 2-in-1 sanitizing and oxidizing chlorine. This shock is quite affordable and quite high in chlorine level. However, it is an unstabilized chlorine shock. That means the UV rays from the sun quickly burn the shock away.
Even though the shock is quite effective in eliminating the bacteria in your pool. The Non-chlorinated chlorine shock on the other hand is also known as potassium monosulphate.
It is also known as an oxidizer and this oxidizer does its job of treating the pool by oxidizing the compounds in the water. This, sanitizing it.
What Are The Similarities Between Pool Shock and Chlorine?
Although different in action, they are quite similar in some aspects. Both pool shock and chlorine kill bacteria. Bacteria cannot stand a chance of combating any kind of chlorine in your pool.
Both pool shock and chlorine chemicals kill algae. Algae normally are usually controlled by an algae ide. However, some early algae breeding can only be removed by pool shock.
Both pool shock and chlorine offer clear, and crystal pool water. The pool shock and chlorine readily break down the water chemistry and balance the unbalanced pool by shocking with the proper shock measurement of chlorine to make the water clearer.
Chlorine is available in granule form and liquid form. Pool shock is also not left out as it is available in granule and also in liquid form.
FAQs
Do you add chlorine or shock first?
Chlorine under no circumstances should be added to your pool first before pool shock. Pool shock should be added first to your pool water. When pool shock is added to your pool, you should wait for some hours until the chlorine level falls below 5 ppm before you can add pool shock to the pool.
Can you swim in the pool after you shock it?
Your pool is safe to swim in once your chlorine levels are balanced. Check if the chlorine level is around 5 ppm. Better still, you can swim in the pool after 24 hours. However, always test the pool to be sure of the chlorine level.
How often should I shock my pool?
Shocking your pool should at least be around once every week. When you notice some funny odor in your pool, or you realize how cloudy and foamy the pool water has turned, then it means it needs some pool shock. Shocking your pool regularly will keep your pool free of contaminants. However, the bottom line is to shock your pool once every week.
How Long does Pool Shock Last?
Liquid pool shock just like liquid chlorine may last up to 2 months. Its shelf life is roughly 2 months because it begins to lose its effectiveness after 2 months is over.
What happens if you go into a shocking pool?
Absolutely something! If you enter your pool immediately after shocking your pool, then it means you are calling for itchy skin and eye irritation.
Is it okay to use an old pool shock?
Old pool shock has a long shelf life. They last up to 3 to 5 years. As long as they are kept in a good place and stored properly in an airtight container, placed away from the rays of sunlight in a cool and dark place. Asides from stabilized chlorine shock, this pool shock lasts for at most 5 years if kept well.
Can you use old chlorine in your pool?
Of course, you can. Old chlorine can be used over and over again. Although chlorine tablets and granules can certainly go bad when left for long without proper storage. So they should be kept in the right conditions and placed well.
How Long Does Chlorine Last in Pool
The type of chlorine can last up to 4 or 5 days. Some chlorine dissipates almost in a day but your pool chlorine lasts for several days.
How Long does Pool shock work?
Pool shock begins work almost immediately until 24 hours is over. As long as you keep your pump and filter up and running, then you should ha e a clean, clear pool in 24 hours. However, if the pool still remains cloudy despite the pool shock, then understand that you need to scrub off stubborn algae from the bottom of your pool and afterward, add another pool shock.
Can you shock a pool 2 times a week?
It all depends on your pool type, and your pool needs. You can shock your pool twice a week or twice in a row. This simply means that your pool is extremely dirty and the pool shock would be good enough to treat the cloudiness of the pool.
Final Thoughts
Pool shock is not the same as chlorine. Pool shock is stronger than chlorine when it comes to usage. Pool shock can easily be gotten from a pool store, as well as chlorine.
They are also quite affordable as well. Pool shock as mentioned above does well to clean up and treat your pool from bacteria, pathogens, algae, etc.
While your traditional chlorine also does its best but then, the best it does is to stabilize the chlorine level of the pool. A pool shock will help a great deal in combating bacteria in the pool. Chlorine is also affordable and time-consuming, especially chlorine tablets.
Pool shock should always come first when it comes to shocking your pool. Chlorine can’t be added first because you cannot possibly, and it may not be able to do the very job of pool shock which is to prepare the swimming pool for chlorine to be added.
Pool shock measurement is extremely important. Try to check out the quantity per gallon of pool size. For instance, per 10,000 gallon pool, you should use about 1 pound of pool shock. Meanwhile, you can always check or ask a pool expert to be sure.
Finally, pool shock is not the same as chlorine but they have striking similarities such that, you might begin to think that chlorine is the same as pool shock when they differ in use.