How to shock an above ground pool : All about Shocking Your Pool 2023

Have you ever felt a hard smell from your pool? What are your thoughts? Is it chlorine or other chemicals?

No, it is not chlorine. Actually, it is the chloramines, which is for the contaminants in water and the absence of free chlorine to make the pool germ free. It is the consequence of the erroneous cleaning of the pool. When chlorine incorporates with other elements (like oil, sweat, urine) in the pool, then chloramines form. On the other hand, it may add the irritability to the eyes and skin.

To avoid these problems you have to learn how to shock a pool correctly. If you are a new owner of a pool, then don’t have to be stressed about the cleaning procedure with the chemical. You will undoubtedly be overcome the fear and be a regular user of the chemical or shocks. Moreover, you will have to know about how to treat pool water for the first time. You will face number of questions in terms of pool water cleaning. These may be

  • What does it mean to shock a pool?
  • What is the best shock for above ground pools?
  • How long does it take to shock a pool?
  • How to put chemicals in pool for first time?
  • How long after shocking pool will it clear up?
  • How often should you put chlorine in the pool?
  • How much does shock for a pool cost?

There is no limit of questions your mind will search for results.

Know about a Pool Shock

You now of course thinking about “What does it mean to shock a pool?”. “Shocking” is a vital task among the pool maintenance procedure. The process means adding the chlorine or other chemicals to the pool water to fix the balance of chlorine the germs, algae, combined chlorine are destroyed by free chlorine. The chlorine or other chemical used for the shocking process is the Pool Shock.

You have to know the difference between the free chlorine and combined chlorine so that you cannot confuse yourself. The whole thing is popular as pool shocking 101.

Pool Shocking 101

Free Chlorine:

It is the part of a chemical that is used for cleaning and sanitizing your pool water. There is a limit. You have to keep the level of FC one to the third part per million. Only then it can do the best job on your pool.

Combined Chlorine:

It issued previously on the pool and remained in the pool. But it loses its power to disinfect the water. So never allow the level of CC to .2 PPM.

Total Chlorine:

Genuinely, the simple math- the total sum of FC and CC. You can have the test kits available in the market to get the amount or level of these chemicals in the pool.

Breakpoint Chlorination:

Try to level the FC higher than the combined chlorine to destroy the chloramines. Always remember that you must add FC about ten times to the CC to balance the level of good chemicals to harmful chemicals. Every time you shock your pool, try to have the breakpoint. Otherwise, your pool will be left with replacing old and polluted water totally. You can do nothing if you do not check it regularly.

Why you Opt to Shock a Pool?

Shocking is a crucial task to do. It doesn’t matter if you install the pool recently. You have to sanitize the water must. The betterment and well being depend on the pool sanitization when the whole family dives down the pool.

The living organism can harm you at the maximum level. Hence, the reasons for shocking your pool are:

  • You cannot imagine that the swimming pools are continually polluting with sweat, oils, germs, urine, and so many uneven organisms. These can be cleared by shocking the water.
  • Sunshine can break your chlorine, and it can lose up to 5 ppm chlorine.
  • Heavy rain and storms also damage the sanitization of the water, so after these incidents, a proper sanitization is needed.

How to Shock a Pool with 6 Steps


Step 1: Choose the Chemicals

At first, you have to choose the perfect shock chemical according to the test results of chlorine and other chemicals in your pool water. There are lots of available shock products in the market. You have to choose according to the types of chemicals and the quality of the product.

Step 2: Prepare the Chemicals

After choosing the shock, you have to prepare the chemical with the manufacturers’ instructions label and maintain the instructions properly. Some shocks can be in the form of tablets and some in liquid, so the quantity of measurement and ways of applying depends on the instructions.

For example, the granular shock should be poured into 5 gallons of water before pouring down to pool water. On the other hand, you can pour lithium hypochlorite directly into pool water.

Step 3: Shock the pool

The first question is, how long does it take to shock a pool? After preparing the chemicals to pour it to the pool water and turn on the filter and pump to spread the whole chemicals all over the pool. Or you can evenly circulate the chemicals in the pool water. If the chemical is in tablet forms, you can use the dispenser or floater to move the chemical all over the pool.

Step 4: Let the Shock do its work

After this, you have to leave the shock in the pool according to the instruction of the chemical purchased. You might think, how long after shocking a pool before swimming. But if it is suggested not to get down the pool water within overnight, then you should maintain it properly. The maximum time that you should take to shock the pool is written too in the shock instruction.

Step 5: Check the Chemical Level of the Pool Water

After all the procedures are done, the pool water must be checked whether the chlorine or other chemical levels, alkalinity, hardness, etc. are in the correct level or not. You have to ensure that all the levels in the pool water should be in a comfort zone to dive into the pool.

Checking the pH level is very important. If the level of pH is over 8, then it becomes extremely harmful. You have to work for it within the score of pH is around 7 so that it doesn’t go higher.

Step 6: Final and Best Filtration System

To confirm the best sanitization, you have to provide a final and best filtration system in the pool to get rid of all the germs. You should run the filter for at least 24 hours to have the best performance.

When to Shock a Pool

There could be arise a question from the new owner of a pool that how often should you shock your pool. Okay, then I can ask you a defensive question that will you shock your pool until the pool water has bad smell or itchy eyes? No, he should not wait up to that situation. Pool shocking is a very common and chemical process to keep pool water healthy and clean.

There is a basic suggestion to shock pool in every week and at max to another week.

  • Don’t wait to let your pool reach the worst position, which incurs more cost and needs more time or even needs draining the pool.
  • The overgrowth of the algae makes the water cloudy, and this would harm your pool immensely. So you have to shock the pool once a week to get rid of the algae and other contaminants and prevent pollution.
  • You have known the free and combined chlorine at the beginning of the article. You should also add the knowledge that the free chlorine should be up at 3ppm. Below 3 ppm chlorine is much harmful for the sanitization of the pool.
  • Don’t think that this is the first diving into your pool; you just installed it today, so don’t need any shock. You must shock your pool before getting down the pool for the first time.
  • Moreover, you have to cover up the pool before the winter. So try to maintain this in a clear position during covering time. Don’t let the germ grow under the cover.
  • Massive storm and rain cut down the chlorine in your pool. So after these incidents, you have to shock the pool to prevent any types of water-borne disease.
  • If your children have a pool party recently in your home, then the pool must be shocked immediate after the party. Don’t let them step into the pools as it would be harmful for them.

When readers of this site buy through our link, as an Amazon Associate, we earn from qualifying purchases. Therefore this affiliate commission never biased our product recommendation. Our motto is to promote the best products for consumers, through detailed research and market analysis.

Different Types of Pool Shock

In the market, there are a variety of chemicals of varying quantity and levels are available. You can choose the products according to your necessity.

1.Calcium Hypochlorite

Calcium hypochlorite is one of the affordable, accessible, and popular chemicals for shocking the pool and disinfecting the water. It is called cal hypo too.


  • It dissolves more promptly than Calcium hypochlorite. So, there is no need to dissolve at the time before pouring it at the pool water. They can mix this directly to the pool water.
  • Most chlorine products, including Lithium Hypochlorite, contains 35% chlorine.
  • You have to wait 8 hours like the previous chemical before starting swimming.
  • Using in dark is more beneficial.
  • It is poisonous for aquatic life, so don’t through the disposed water where aquatic life can be possible to live.
  • There may be a shortage of the Lithium Hypochlorite for extending price, and it is also used to make lithium battery in a great deal, so can experience the lack of this chemical for shocking in the supply market.

2.Sodium Dichlor

Sodium Dichlor shock is much easier to use and dissolve in a longer time than Calcium hypochlorite. The actual name of this is quite long as sodium dichloro-s-triazinetrione or dichloroisocyanuric acid.


  • Most chlorine products, including Sodium Dichlor, contains 35% chlorine.
  • Depending on the brand’s instruction, you may add it with water to dissolve before some time ahead of pouring to pool or directly add to the water.
  • It adds cyanuric acid with water for every ppm of Free Chlorine.
  • Use it after dark time for the best performance.
  • Wait for 8 hours to swim after the usage of the chemical.

3.Potassium Peroxymonosulfate

It is a non-chlorine shock. It works faster and costs less than the previous chemicals.


  • It is oxygen-based instead of chlorine-based.
  • It works by oxidizing the pool and thus accelerates the chlorine level.
  • You can swim immediately after the treatment, but 15 minutes is the least time to wait if you wish.
  • You can add the chemical directly to the pool water.
  • Remember that it doesn’t work as an algaecide.

When readers of this site buy through our link, as an Amazon Associate, we earn from qualifying purchases. Therefore this affiliate commission never biased our product recommendation. Our motto is to promote the best products for consumers, through detailed research and market analysis.

Some Tips for Shocking and Preserving the Chemical

    • Always remember all of these are toxic chemicals and may blast if you cannot correctly handle those. Follow some tips while using those products.
    • Calcium hypochlorite may take out a minimal amount of chlorine gas occasionally. So, put on the protective gears like goggles & chemical resistant gloves to prevent skin irritation and eye irritation.
    • All the stated chemicals are different from one another. So never try to mix this chemical with one another and never try to do any home experiment as your home is not a lab. Always add the products separately.
    • It is better to wear a dust mask as the smell of chlorine gas can cause lung or throat irritation. Don’t be too close to the boxes.
    • Don’t open several containers at a time, even if you think you will need all. Always make one box empty then go for other ones.
    • Remember to follow the instructions stated in the bottle. Each brand is different from one another. If it says to dissolve before adding to the pool, then do this.
    • You may keep the pool uncovered until the average level of chlorine. You have to ensure that the chlorine level is less than 3PPM.
    • Windy days are not perfect for shocking. This can blow the shock to your eye and body.
    • After shocking the pool, try to clean every pool accessories with cleanser. Shock the pool once per week. After shocking, you can brush the pool ground to get rid of any residuals.

Following are the comparisons among all the products discussed above.

CharacteristicCalcium Hypochlorite (Cal Hypo)Sodium DichlorPotassium Peroxymonosulfate
Chemical TypeChlorine-basedChlorine-basedNon-chlorine (oxygen-based)
Dissolution SpeedRapid, no pre-dissolving neededSlower, may need pre-dissolvingRapid, direct addition
Chlorine ConcentrationContains 35% chlorineContains 35% chlorineDoes not contain chlorine
Best Time for ApplicationAfter darkAfter darkCan be applied anytime
Waiting Time Before Swimming8 hours8 hoursMinimal (around 15 minutes)
Impact on Cyanuric Acid LevelsIncreases CYA levelsIncreases CYA levelsDoes not affect CYA levels
Compatibility with AlgaecideNot mentionedNot mentionedDoes not work as an algaecide
Impact on Aquatic LifePoisonous for aquatic lifeNot mentionedNot mentioned
Availability ConcernsPotential supply shortages due to other usesNot mentionedNot mentioned


Frequently Asked Questions for how to shock a pool

What is the best time of day to shock pool?

Regularly you may wash your pool with shock at any time of the day. But it is recommended to use after dusk or in dark times. Moreover, the shocking can be done entirely in the overnight. So you may get some more time to get yourself free to jump in the pool to swim.

Additionally, the harmful UV rays of the sunburn the chlorine and damage the effectiveness in a general level, so sunlight is not beneficial for the shocking of the pool.

Is Shock and chlorine the same thing?

Chlorine is an effective way of disinfecting the pool. Shock products always include the chlorine chemical, and in fact, significant of the shock products include chemicals. But there are some shocks too which have different chemical than chlorine or chlorine less. These can affect the pool with sanitization but not like chlorine.

Does a shocking pool raise chlorine? or How to raise chlorine level in pool?

Yes, it raises the free chlorine. But it is not harmful. In fact, different shocks have a various amount of chlorine left in. So this will increase the chlorine in a different level. Shock increases the pH level of the pool water along with the increased level of free chlorine too. The level of chlorine shock keeps a balance between the free and combined chlorine. Thus shock maintains the sanity of the pool.

Will shock clear a cloudy pool?

Obviously, a significant task of shock is to clear the cloudy pool. The dose of chlorine and chlorine-free treatment both can make the murky water clear in this term. The cloudy tendency occurs for the bacteria, algaecide, and other microorganisms. Shock can clear all of these and make the water crystal clear.

How much shock does it take to kill algae?

It usually is instructed in the container of every product that how much should be needed and how much time you should wait. Usually, 1 pound of shock may be enough for per 10000 gallons of water and takes 10 hours to shock the pool. It is the estimation in a general manner.

Can I shock my pool in the rain?

It is necessary to shock the pool after heavy rain. Shocking in the rain doesn’t bring any good thing but you must shock the pool after rain. Rain may bring some uneven elements and algaecide in the pool water, so the pool needs a shock every time after heavy rain.

Liquid chlorine vs powder, which is better shock?

There is not much variety in the activity. Liquid shock is of fewer prices than powder shock, and it comes in refilling options. Liquid forms are already in liquid form, so you do not have to mix with the water. You can pour it into water directly.

How long after shocking a pool before swimming?

The answer depends on the conditions where you have used chlorine or not. If you used chlorine, then you will have to wait at least 12 to 24 hours to swim safely. On the other hand, if you chose the non-chlorine shocking process, then you will feel to jump just after completing the shocking process.

How much chlorine to add to pool?

There are few issues to cover the answer of this question. The filter machine is related to the chlorine amount. If you want to add chlorine when the filter is running, then the amount will be a little bit different from if the filter is not running. Moreover, the amount mostly depends on the size of the pool. The chlorine amount will be needed around 52-1-4 oz of liquid chlorine per 1,000 gallons of water. The chlorine level should be between 5 to 10 parts per million(ppm) with this chlorine amount.

How much liquid chlorine to add to pool?

The general equation about the amount of chlorine to shock a pool with algae is about 30 parts per million(ppm). If we assume that your pool is clean, clear and already pH has been adjusted, then you can add that amount of chlorine. Usually, there is pool shock packages state addition of 1 lb. shock in every 10,000 pool water gallons.

What happens if you swim in a shocked pool?

Though I can answer this question, before that I want to ask you a question also. Why do you think swimming just after shocking the pool? Is it natural thinking? No. Every work process has its own way to complete, so be cool and patient to do the pool’s own work to complete the shocking.

Okay, now you again can ask the same though you were forbidden to swim after the pool shocking. Now, I have to go in detail to make you aware of the swimming in a shocking pool.

You know, pool shock is a chemical process to kill the germs, algae, and bacterias for keeping control of the debris from perspiration and deterring algae. As chlorine is a material with a very strong odor which could make your eyes redden, it could cause allergic reactions, so no one should swim in a shocking pool.

Dryness of your hair, skin also could happen for this un suggested swimming in a shocking pool. As chlorine causes harm to your skin, there is also a question about your fertility issue. Moreover, long term asthma, irritation, skin as well eye irritation could happen for doing this in an unprescribed way.

So, no one should swim in a shocking pool.

Can you shock a pool without the pump running?

Yes, I can shock the pool without the pump running. Actually, it is not the usual incident. It could happen very often when the pump does not work properly or broke down. So, if there is an emergency, you can shock the pool without using the pump. On the other hand, if you can wait for a few days to repair or to get help from a professional, then I would suggest you rather wait.

Why am I not inspiring you to shock the pool without running the pump? Yes, that will take huge physical labor to shock your pool properly. Okay, you still shock the pool, then the following steps you should follow:

  • Test the pool water
  • Add chlorine as instructed
  • Brush the pool wall very well to keep away the floating-issue
  • Remove leaves and check out the skimmer basket
  • Manual vacuum
  • Run your robot cleaner
  • Don’t Wait when you get back of your pool pump

# Test the pool water

Before doing the testing process of your pool water, you will have to have the required knowledge about testing pool water. After reading the full instructions, you can do so.

Here, you can ask a question on how often I should test the pool water. Then, my answer is if possible then try it every day. But the reality is without a commercial pool, the owner does the test 2-3x per week.

The list of water test is like

  • pH: 7.2 – 7.8
  • Chlorine: 1.0 – 2.0 ppm
  • Total Alkalinity: 80 – 120 ppm
  • Calcium Hardness: 200 – 400 ppm
  • Cyanuric Acid: 20 – 50 ppm
  • Total Dissolved Solids: below 5000 ppm

# Add chlorine as instructed

The major challenge at the time of adding chlorine is to circulate the water as you don’t have the pump at that time. You have to follow the instructions to add the chlorine using shock or liquid chlorine and at the same time, you will have to circulate the pool water. Because of circulating the water, the chlorine will not be centered into a single spot and will be good for any damage.

# Brush the pool wall very well

By brushing the whole pool repeatedly means one to two in a day will help to keep the water moving and it also helps to remove the particles.

# Remove leaves and check out the skimmer basket

Now, you will have to scoop the leaves or any other particles, remove those from the so that all kinds of bacteria and algae will be in lack of food.

# Manual Vacuum

After the shocking process, you should go through the manual vacuum which will help to clear a few dead algae. The floc will help to drop out the suspended particles to the floor of the pool for safe and easy vacuuming.

# Run your robot cleaner

You must have a robot cleaner to clean up the pool by circulating and filter the pool water. You will have to keep running the robotic cleaner to continue its task. You should be sure to clean up the cleaner’s filter bag as well as cartridge regularly.

# Don’t wait when you get back of your pool pump

After receiving the pool pump or when the professional people reach your pool, don’t keep them waiting to make the formalities. Just start the pump and let’s do its pending work to complete the task perfectly.

How long should I run my pool pump after shocking?

Let’s talk about human nature. What do we people do? We usually want to save money and hassle. That’s why we the owner of a pool follow all respective steps for shocking the pool like water testing, add chemicals, scoop leaves, remove those bacteria and dead algae, and then wait for a couple of hours to complete the pool shocking process.

After that, we usually feel, ‘Uf, last of all, I complete the task’. Hahaha, though the total process is not yet done as there is a major part of filtering. We then start the pump before going swimming.

One of the most important parts of pool shock is to keep running the pump with a filtration system. But the most common mistakes we do that don’t feel like keep running the pump enough time as a requirement.

Okay, then the question is, how many hours I will have to keep running the pool pump.

Yes, you will have to keep running the pump at least 8 hours a day. You will have to run your filtration system twice a day so that the water will be as clean and clear as before.

The pump running time should be based on the pool size. But the usual calculation is as above.

If the pump runs more then the whole water of the pool will be filtered through the filter and then the water will be crystal clear.

How long should you run filter after shocking pool?

Before starting to give the answer to the above question, we should have an idea about the differences between the pump and filter.

What does a pump do? The pump does nothing but moves the pool water to the filter for filtration. So, the circulation of water creates when the pump runs.

On the other hand, what do we mean by a filter? The filter means the way of purification by removing unwanted particles.

Now, you can also ask “Can they work separately?”. The answer is “No”. Filtration is not possible without running the pump and vice versa without having the filtration system, there is no fruitful output by running the pump.

So, if a question comes like “how long should I run my pool filter each day?”. Then the answer is the same as for the question of “How long should I run my pool pump after shocking”.

Can I add shock and chlorine at the same time?

Before knowing the answer to this question, we should know what it means by the terms “Shock” and “Chlorine”. The Shock and the Chlorine are very much interrelated to each other when there comes the issue of pool shocking.

Chlorine is referred to as sanitizer which is a must for keeping the pool healthy and clean whereas the shock is treated as a granular oxidizer is a powdered form of chlorine is used to raise the chlorine level quickly.

In order to keep the pool water healthy and keep the chlorine level between 1 to 3, you will have to use both, the chlorine tablets as well as the pool shock. Without the shock, the chlorine level will be at a low level to complete the full sanitization. On the other hand, the chlorine shock will be not in a good position without chlorine tablets.

The measurement of pool shock is very important and you will have to measure the quantity of shock very carefully. If you add chlorine where the shock is also running, all the arrangements and results will be zero.

So, it is recommended not to use the shock and chlorine at the same time. After completing your pool shock, it is all over everywhere recommended to add chlorine.

Final Words

I think I have been able to make you understand the mathematics of when, why, how, and how many times you need to shock your pool. Starting with the measurement to the time table, all you need to be a little bit analyzer. Then you can make the overall shocking and cleaning task regularly with the best performance and with no more cloudy water.

Don’t take stress about the system; you may hesitate to do this for the very first time, but the more you shock the pool, the more you will be expert in shocking the pool. Swim happily in the germ-free clear water.