How Often Should I Shock my Pool

Why might you have to perform pool shock? The pool shock process works to remove combined chlorine molecules, which you commonly referred to as a Chloramine.

More so, pool shocking occurs to help remove excessive bather waster and bacteria levels, especially if it’s a high traffic pool. Plus, the process also works to help remove visible algae and contamination events that might occur. Bromine treated pools and spas also implement pool shock techniques to help restore bromide ions’ functionality.

There are three main reasons as to why you may have to perform a pool shock process:

  • Algae – green, pink, black, or yellow, the best way to exterminate such a problem would be to raise the Free Chlorine level (10-30ppm). Why? Because it will help to oxidize or exterminate these contaminants. You can control the development of pool algae by using some algaecide. That said, to exterminate algae and clean the pool, the best solution would be pool shock. Ensure that you adjust the pH range to between 7.1 – 7.3. Making such an adjustment ensures the chlorine is potent. Killing algae blooms will require, on average, between 10-30ppm. Also, chlorine accelerators such as Yellow Out are ideal for promoting chlorine levels to exterminate algae blooms.

  • Bacteria and bather waste – bacteria can also get to the pool through several sources, with most of them being relatively harmless. That said, pathogenic bacteria are also common. Use chlorine shock techniques to help eliminate bacteria after excessive use, long winters, heavy storms, etc. Plus, bather waste includes products such as cosmetics, soaps, hair, lotions, and more.

  • Chloramines, contaminants, and cloudy water should know that combined chlorine molecules are responsible for the “red-eye” side effect and strong chlorine smell. The solution at this point would be to ensure chlorine levels don’t surpass the 0.5 ppm-level. If this is the issue, then add some chlorine and non-chlorine shock. These products will work well to regulate the amount of combined chlorine in your swimming pool.

The Important Facts When Using Pool Shock

Pool shock is a process pool owners, and contractors use to eliminate contaminants from swimming pools. There are lots of harmless matter that will get to your pool, and compromise the balance of water. You can correct cloud water with super chlorinating techniques, or by adding chlorine oxidizer. These are chemicals that ensure you can destroy colloidal particles that can lead to cloudy water.

Put merely, chlorine shock works best for exterminating algae and bacteria. On the other hand, non-chlorine shock offers the best Chloramine and Contaminant removal results. Below are some of the common points in time you should expect to use pool shock:

  • Startup and close down – for pools that are winterized, opening the pool will be the first time when you use pool shock when the water chemistry level is correct. Using it at such a point ensures it oxidizes the particles, exterminates bacteria, and algae – perfect for restoring the water’s clarity. Before you decide to shut down the pool for the season, consider using pool shock to make things convenient for the upcoming season.

  • Heavy rain – rain is pure water, which undergoes distillation through evaporation. That said, it may pick up airborne particles as it falls through the air to your pool. Many issues might compromise water quality. These include dust, pollen particles, algae spores, and more. More so, during heavy rain, overhanging trees, large plants, or yard spaces that are close by might also compromise the water quality.

  • Chloramines – free chlorine converts to combined chlorine when it mixes with ammonia or nitrogen. The bond causes the chlorine molecule to become useless, causes a strong smell of chlorine, and irritates swimmers’ eyes. Using DPD tests, kits will be beneficial for determining Free and Total chlorine. You may have to use pool shock to remove chloramines when the levels surpass 0.3 ppm.

  • Other applications – for pools that have several users, or pools that are contaminated with urine, vomit, or feces, shocking is the best solution in cases where the chlorine levels depleted, due to issues such as hot temperature, faulty equipment – using pool shock can be an excellent solution.

How Frequent Do You Need to Shock A Pool? 

Each pool is unique, and there are various factors to consider before performing pool shock. It’s a process that works to remove bacteria, chloramines, and various types of contaminants. Also, pool shock is a process that helps remove cloudy water or various other water complications. The presence of algae should be a strong sign of pool shock effectiveness. That said, pathogens and other bacteria are not visible to the human eye. Thus, many pool owners recommend shocking pools after 3-4 weeks, even if the water is clear and clean.

Chlorine vs. Non-Chlorine Pool Shock

When using any of these products, it’s good to follow the instructions on the package. Usually, it will provide useful information on the length of time to wait after shocking, before getting into the pool. Using large amounts of granular chlorine needs a large timespan (24-48hrs) before the pool is safe enough to use (5ppm). Before using the pool, ensure you determine the nature of the product used for the best results.

Even more, chlorine-free shock treatments contain potassium and various salts. More so, it also offers various other benefits that you would not necessarily get with chlorine-based pool shock techniques.

These products’ strengths vary in relation to brands, but most non-chlorine products contain 37% – 42.6% Potassium Monopersulfate, aka MPS.

Non-chlorine Shock Pros

  • Quick-release, potent, no odor and residue

  • No pre-dissolving required and you just pour into the pool

  • Eliminates ammonia and toxic products

  • Won’t fade or bleach items such as swimsuits or vinyl liners

  • You can use them immediately with no waiting times

  • Does not add cyanuric acid or calcium to the pool

Non-Chlorine Shock Cons

  • Not as powerful for algae and bacteria treatment

Chlorine Shock Treatments

These are available in two common types – the Dichlor and Cal Hypo. Using calcium hypochlorite is the most popular, potent, and cheapest solution for pool shock. Usually, the two categories of these treatments include the Shock and Super Shock. Plus, Dichlor consists of stabilized granular pool shock, which is produced by the stabilizing compound. Such a technique ensures the product is safe from direct sunlight or exposure to moisture.

Chlorine Shock Pros

  • Fast-acting and quick release

  • Removes ammonia and chloramines

  • Eliminates bacteria and algae fast

  • Cheapest method for shocking the pool (Cal Hypo)

Chlorine Shock Cons

  • Pre-dissolving granular is ideal for protecting the surface

  • Waiting for 24 hours is recommended

  • High levels of chlorine can be harsh on some surfaces

Estimating Pool Shock Amount

How much pool shock should you use? You may first have to determine the amount of water in your pool. If you are not sure, take some measurements, and consult a local swimming pool contractor. Usually, the dosage amount of pool shock averages at 1 lb. Per 10,000 gallons. That said, ensure you check the labeling of the package before using the product. The dosage amount recommended for a specific pool depends on the severity of the contamination.

When it comes to removing chloramines, shock the pool until it reaches the Free Chloramine level. Usually, this amount ranges between 10-20 times the amount of measured chloramines used in the pool shock process.

For the removal of chloramine, shock the pool until it achieves a Free Chlorine level, and it should be 10 to 20 times the amount of measured chloramines. To remove algae, 30ppm is usually accepted, but you can also use more or less. Plus, it also depends on the severity of the algae bloom.

You can use various resources to calculate the amount of pool shock you need to treat your pool. Plus, if you still notice the watercolor is still green, then this shows the water is compromised with algae. Thus, you might have to use more of the product. Check with your product labeling or a local contractor on the specific chlorine amount levels to use.

Pool Shock Longevity

What is the longevity of pool shock? Storing pool shock products in the cold and dry places is crucial in maintaining their potency. Additionally, storing the product in a garage or store can easily compromise its quality. Thus, storage is vital if you want to keep granular products in storage.

Remember that plastic bags are also prone to damage. Thus, for the ideal storage results, it would be good to use Cal Hypo Buckets. Ensure the lids are tightly sealed to keep out moisture accumulation.


Taking good care of your pool is an essential factor to consider. Why? If you want to avoid dirty water and health complications, it’s best to make an informed decision for your pool each time. Thus, this is why we have discussed the topic,” what is pool shock.” It’s simply a process that you use to clear your contaminants pool that might lead to health issues.

How to Shock a Pool

Have you ever wished that your pool gets rid of the lingering algae? Did your friends complain the last time about the odor coming out of your pool? Do you want to eradicate this menace of algae once and for all?

Well, if that’s the case, you have landed at the right place. In this article, you won’t only learn how to shock a pool, but to do so at a remarkably economical price. As a result, you will succeed in your quest of getting a cleaner, user-friendly outdoor pool.

Before we shed some light on how to shock a pool, let’s take a look at some of the other queries which are associated with the shocking.

Some Prerequisites for Shocking

Carefully choose the time for Shocking

As far as most experts are concerned, they recommend that we shock the pool at night. This is done to help the chemical which is used for shocking. For example, chlorine is the chemical which is used most often for shocking.

In order to get the maximum results from chlorine, you need to do the task at night. The reason for this is simple: in the broad daylight, the sun eats the chlorine. Therefore, in order to save your time and money, I would recommend that you shock your pool at night.

Carry out a test for recording the chlorine demand of your pool

Although pool shocking sounds very easy, people who have actually done it believe otherwise.

The main problem which the majority of first-timers encounter in their first attempt is when, despite adding chlorine, the amount of algae remains the same in water. This happens because they haven’t tested the chlorine demand of their pool.

Chlorine demand is actually the amount of chlorine your pool needs in order to convert all the bacteria into chloramines. These chloramines will be diffused into the air. Unless you haven’t satisfied this demand, no pool shocking chemical will come to your rescue.

Hence, before doing anything, purchase a pool water test kit from the market. While this won’t help you in shocking the pool, it will give you the chlorine demand of your pool.

Use a few protective equipment

Since you’ll be dealing with chemicals in the concentrated form, use gloves and goggles in dealing with them. Moreover, try to use worn out clothes during shocking. This is due to the fact that the chlorine granules are concentrated, and they will most probably make holes in your shirt.

How many Packets for shocking? Decide wisely

According to the standard, one packet of shock, which normally weighs 1 pound, should be enough for 10,000 gallons of water. Therefore, before going out in the market, get a raw estimate of the gallons that your pool is holding. For this purpose, you could use the pool volume calculator.

Dissolve your shock packets in water – and not the other way around!

Take a bucket, fill it with water and add the shock packet. Remember, water first – chemical last. Once you have added the shock packet into the bucket full of water, gently stir the water to dissolve the packets.

Slowly pour the Mixture into the pool

Once you have made the shock solution as per the manufacturer’s recommendations, pour it slowly into the pool. Avoid splashing or throwing the water into the pool. After you have done this, all you have got to do is to wait and let the chemical do the magic.

Different types of water – and how to select the Chemical in each case

You might have noticed that while your pool is light green, that of your friend is black green or darker in color. The difference comes from the amount of algae which has accumulated in the pool.

Therefore, before telling you how to shock the pool, it is very crucial that you choose the optimum amount of chemical in each case.

  • For Light Green Water:

If the water is light green, it means there is a very low amount of algae in your pool. Consequently, you won’t have to use extravagant amounts of chlorine to shock. Thus, 2 pounds per 10,000 gallons will do the trick.

  • For Dark Green Water:

If the water is dark green, it means that medium amount of algae is in your water. Therefore, you will need to shock your pool thrice. For this, you’ll have to add 3 pounds of chlorine per 10,000 gallons of water.

  • For Black Green Water:

This is the worst case scenario. It means that your pool hasn’t been cleaned in ages. In other words, you will have to spend some extra bucks to shock it. Thereby, for a pool which contains black-green water, 4 pounds of chlorine are required per 10,000 gallons of water.

Once you have shocked the pool, your pool water will acquire a cloudy blue color. There’s no need to worry as the appearance of this color indicates that shocking has been successful.

Different types of Chemicals you could use in Pool Shocking

As you might have noticed in your market tour, there is a myriad of chemicals available in the market. Since all of these chemicals won’t help you, below mentioned is a description of compounds with their pros and cons …

  • Calcium Hypochlorite ShockIn case you don’t want to take any risk, calcium hypochlorite shock is a must-have for you. With all-round properties, 65% chlorine and lots of calcium, this chemical is best for almost all types of pool water. However, it comes with a caution. After you have shocked the pool with calcium hypochlorite, don’t use it for at least 8 hours.
  • Lithium Hypochlorite ShockIn such a case when the water testing has revealed the presence of calcium in your pool, you don’t need to spend amount to add extra calcium to it. In such a case, go for the calcium-free, Lithium Hypochlorite shock. However, you still won’t be able to use the pool for 8 hours after adding the chemical into it. .
  • DiChlor ShockIf you live in a hot area, DiChlor shock might save you a lot of money. The sun oxidizes chlorine mitigating its effectiveness. Thus, in order to support chlorine, a dichlor shock could be used.
  • Non-Chlorine ShockFor people who want instant results, use the non-chlorine shock for their pool. Containing a large amount of bromine, this chemical could be added to your pool at any time of the day. Since the sun won’t be able to oxidize bromine, the chemical will remain intact even in broad daylight. Moreover, after shocking the pool with bromine, you could jump into it within 15 minutes.

Now that we have settled different queries, let’s move on to the major part telling how to shock the pool.

How to shock your swimming pool step-by-step guide

  • Step#1: Test the water

As mentioned in the above mentioned description, the number of algae are crucial in deciding whether your pool shock will succeed or not. Therefore, before you decide on the amount of chemical, I would recommend using a water testing kit for pH testing. Before you have added any chemical, the pH will be very low.

After shocking, the pH will go high. However, in order to prevent it from being too high, test the water before starting the shock.

  • Step #2: Use a Pool Brush to scratch the algae of the walls

As you might have seen yourself, the favorite habit of algae is to cling to the walls of the pool. Therefore, in order to have the maximum effect of shocking, brush the walls of the pool to scratch algae off it. Look for areas where algae most often reside i.e. pool steps, behind ladders, crevices, and creases.

  • Step #3: Purchase a 25-Pound container of Chlorine Granules

Once you have ensured that the pH is less than 7.2, which means that the water is slightly basic, start to shock the pool with chlorine. Instead of purchasing the usual 1pound bags that are available in the market, I would recommend you to go for a 25-pound container.

As you might guess, you’ll get a lot of subsidy by buying such an amount at once. More importantly, you could be assured that your pool would not remain under shocked.

  • Step #4: Distribute the chlorine evenly over the water

The greater the surface area that you will allow the chlorine granules to function, the greater will be their rate of reaction. Consequently, fewer pounds of chlorine will oxidize more amounts of algae. Thus, after setting the filter pump on, distribute the granules of chlorine at all corners of the pool.

  • Step #5: Don’t cover the pool during shocking

If your pool is indoor, make sure to turn on all the exhaust fans. If it is outdoor, DO NOT cover it for at least 1 day. The reason for this is simple: after shocking, Nitrogen will be released from the pool in the form of a by-product. Since it is an inert gas, it will be in your best interests if you allow it to diffuse into the atmosphere.

  • Step #6: Pumping and Filtering

Although there are many types of filters used in swimming pools these days, almost all of them function similarly when it comes to pool shocking. Thus, be it the DE filter, the Sand filter, or the Cartridge filter, you don’t have to make any extra effort before using them after shocking.

However, having said that make sure to backwash the filter before shocking the pool. Afterward, when filtering out the water after the shocking, make sure there are no obstructions in the way of the drain.

Keep the filter running for at least 24 hours or until the pool is clear. If you want urgent results, add a water clarifier. It will speed up the process.

Bonus Tip: If you want a visual description on how to shock a pool, check the video below:


While you might gauge from the above-mentioned description that pool shocking is a time-taking task, the best thing you could do to save time and money is to take some extra care. For example, during the season, run your filter 8 hours daily. Try to keep your pool clean by brushing and vacuuming daily. These little things will save a lot of time and money.

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