Swimming pools require a series of maintenance processes to attain a state of stability without posing health issues to the users.
While some are preventive measures like eliminating potential means of dirt entry, applying chemicals to the swimming pool can get tougher.

You can’t escape the reality of doing these; nonetheless, it is relatively easy with appropriate knowledge in place.
Now, you must have heard about the shocking swimming pool. It is common for people to give out information without giving further instructions on actualizing their idea.
You are either in the league of those who get information from those mentioned above or don’t pay attention during the conversation.
Table of Contents
How Much Pool Shock Do You Need In Your Pool
You need to be aware of your swimming pool’s volume. For a 10000 gallons swimming pool with no issue, the recommended is 1 lb. of pool shock. If there is a presence of visible algae, use 2 – 6 lb. of pool shock for the same volume of water. For the algae, the amount of pool shock depends on the level of algae bloom in the swimming pool.
The goal is to reach 10 – 30 ppm before it eventually returns to a normal 3 – 4 ppm level. In addition, if you can’t get up to this range, you need to take turns of pool shock.
You can double or triple shock your pool for some conditions like foul-smelling pools, strong violent storms, someone messing up the water with feces, urine or vomit, and other things. If your pool remains green, black, or whatever color your algae appears, you still need more.
A swimming pool with a high pH makes shocking as effective as it should. You need a pH of around 7.1 – 7.3 for enhanced and optimized shocking processes.
If the pool pH is far away from this range, you are more reliable to miss the mark. You might get more chlorine content than required or use more pool shock than normal.
Read: How Much Shock Do You Need For Your 1000 Gallon Pool?
Shocking is a chemical process whereby granular or liquid chlorine is added to the swimming pool’s water.
With algae, bacteria, fungi, pathogens, and general chloramines in the swimming pool’s water, shocking gives an enhanced solution of destroying these and creating an environment that wouldn’t accommodate their breeding.
Since it involves chemical proportion, you should first guess the amount of shock to be added to your swimming pool depends on the size of your pool, the product or type of shock you use, the chemical condition of the water, and the environmental exposure to the swimming pool encounters.
You are right, but it also depends on the expertise of the person in charge of maintenance and the methodology they use to avoid errors in the usage.
Why Should You Shock Your Pool?
Swimming pools are open to vast conditions and are highly vulnerable to attacks due to the pH they normally sustain. A lot can breed in the water, and there will be slight differences in the water condition over time due to these invasions. That is basically why shocking is needed.
Shocking removes waste combined with chlorine molecules, chloramines that would have formed after various chemical balance processes in the swimming pool’s water.
They also clear off bathers, contaminations, and bacteria in the pool after maybe a pool party, excessive swimming sessions, after a heavy storm, raining period, or when there are visible algae in the swimming pool.
Pools treated with bromine (an alternative for chlorine in clearing germs) are shocked to activate the bromine ions introduced into the swimming pool.
In a glare, raising the free chlorine level of a swimming pool above 10ppm to 30ppm should be targeted at the following:
- Low level of chlorine: After testing your pool, consider shocking the pool if the chlorine level falls below two ppm.
- Presence of algae: Algae exists in different colors, mostly black, green, and yellow. Algaecides will kill algae off, but a pool shock will also clear the swimming pool amidst taking this function too. In cases of algae blooms, Pool shocks are combined with chlorine accelerators to destroy the algae to zero fully.
- Chloramines: Chloramines can cause shortness of breathing, choking, sinus congestion, eye irritation, wheezing, asthma, and many health issues if cases of exposure. It is formed when ammonia is introduced into the swimming pool, and it reacts with the chlorine available in the water. Over time, it naturally forms, and when the level is higher than 0.5 ppm, it will take a heavy load of chlorine to dissolve and neutralize it. This can only be done by shocking.
- Bather waste and bacteria: In the event of swimming, there is the release of bacteria and chemicals from hair sprays, cosmetics, lotions, and skin shavings contributed by swimmers. It can also be from an environmental influence like rain or storm, which either comb in exterior materials in terms of a flood or by dropping twigs and others through the wind. Some bacteria are harmless, but pathogens also form in the process.
- Starting up a swimming pool: Whether after winter or a new swimming pool opening, pool shock plays the role of disinfecting the water present and making it ready for usage.
- Cloudy, malodorous, foamy, or green water: This can result from a lack of required chemical balances, faulty filtration facilities, or algae bloom caused by environmental influence. After applying pool shock, the surface and the observed dirty content will be cleared off.
Read: Can You Mix Bleach And Pool Shock?
Chemicals Needed To Shock Pools
Pool shocks come in two different forms: chlorine pool and non-chlorine pool. Swimming pools are usually being maintained with bromine or chlorine, and you are open to using a variety of products for your pool.
In case of any special treatment in your swimming pool, you should try to contact your pool maintenance company or store for recommendations based on the product you use.
Selecting a pool shock depends on your pool material type, maybe vinyl, concrete, or fiberglass, and the water condition of your swimming pool. Pool shocks might be classified into liquid and granular pool shocks, but you should focus on the chemical constituents.
- Sodium Dichloro-S-Triazinetrione: On labels, you might have “Sodium Dichlor” or “Dichlor.” It has inbuilt cyanuric acid to add to the swimming pool as a conditioner for protection from ultraviolet rays and quick evaporation. It has 56% chlorine strength and is a stabilized pool shock. It has no contribution to the pH of the swimming pool, nor does it contribute calcium in the process.
- Calcium hypochlorite: Not stabilized as it has a pH of 12 and can alter the general pH of the swimming pool. It is the most common, less expensive means to shock your pool. It has a chlorine content of around 64% to 73%.
- Potassium monopersulfate: Non-chlorine formula, good oxidizing agent, and partly toxic if used in inappropriate portions. It eliminates bather waste, clears off algae, and facilitates water clarity. Non-affected by sunlight and typically doesn’t leave a residue of cleared content.
Which Chemical Should I Use To Shock My Pool?
- Calcium hypochlorite is usually used in commercial swimming pools for its efficiency in supplying a wide range of chlorine needed daily.
- Potassium monopersulfate is effective in vinyl pools because of its interactivity with the liner.
- To avoid distortion in calcium levels, Sodium Dichlor will be preferable.
- Swimming pools with high cyanuric acid levels should be shocked with other products apart from Sodium Dichlor. It raises the level of cyanuric level bit by bit during application.
Advantages of chlorine pool shock
- Cheapest pool shocks yet very effective.
- Easy to get in pool stores.
- Quick-release of constituents during reaction with the water.
- Begins impact immediately after introduction.
- Destroys organic contaminants.
- Work best for chloramines and ammonium.
- Disinfect bacteria and algae in the swimming pool easier.
Disadvantages of chlorine pool shock
- Swimming pool water remains a bit cloudy, and the residue is left after impact.
- The high chlorine content they contribute to a reaction will negatively impact some surfaces. Chlorine-based pool shocks aren’t recommended for vinyl pools.
- There is a need for a pre-dissolving granular for efficiency for surface protection.
- Toxicity can cause health issues in exposure or contact with human body parts.
- A strong odor is hard to store due to its reactivity to different conditions like moisture, heat, sunlight, etc.
- Calcium hypochlorite gives out calcium and, as a result of this, causes disorientation in pools with normal levels of calcium.
- Sodium Dichlor produces cyanuric acid, which will increase acidity levels significantly if used in large quantities.
Advantages of Non-chlorine pool shock
- Non-chlorine pool shocks are manufactured with a balanced pH level. They, however, don’t have any effect on the pH of the water.
- Doesn’t require any pre-dissolving substances before application.
- It can be used without any complications.
- It doesn’t react with the swimming pool wall or pool ladders and rails.
- Swimming can proceed almost after applications, but it is advised to have a little time to spare for proper effects.
- Kills bacteria and algae.
- Disinfects the swimming pool’s water easily in a fast mode.
- Non-chlorine pool shock doesn’t wear bleach swimsuits or pool liners.
- Eliminate ammonia, nitrate, and chloramines generally.
- Leaves no residue.
- Organic contaminants are oxidized for the purification of the water.
Disadvantages of non-chlorine pool shock
- The concentration of chlorine is lower than in chlorine pool shocks.
- The impact on bacteria and algae is not as effective as chlorine-based pool shocks.
Read: How Much Shock Do You Need To Open Pool?
How To Shock A Pool (Step By Step Process)
There are different approaches to shocking a pool, and they depend on the type of shock you have. While your product’s manufacturer will give instructions on the processes, chlorine-based pool shocks need a dissolving medium while non-chlorine pool shocks can be applied directly.
General pool shock application:
- Test the pool’s pH and try to balance it between 7.1 and 7.3.
- Run the filter system and try to clear off all dirt, debris, and anything your filter facility can obtain. Then of it.
- Determine the quantity required for your pool size and situational characteristics.
- Follow the manufacturer’s manual instructions and prepare your pool shock for application. There is a guide if you are using a chlorine-based pool shock and you need to go about dissolving granules.
- Please make sure the sun isn’t up as it will induce the effectiveness of the shock.
- Pour your pool shock into the swimming through the edges.
- Run the filter system and brush through the swimming pool to facilitate circulation.
- Turn off the filter after a few
For dissolving chlorine-based pool shocks:
- Get a 5 gallons bucket.
- Fill it with clean water.
- Pour 1 or 2 lbs. of pool shock into the water.
- Stir it with a stick or any suitable paddle you can get.
- After evenly dissolving the granules in the water, pour them into the swimming pool through its edge.
When will you be able to use your swimming pool after shocking?
For non-chlorine pool shock, you can swim after a few minutes of application or according to the manufacturer’s instruction.
You can only swim after 24 hours of application for chlorine-based pool shock. In some cases, the chlorine level will still be more than 5 ppm, and the pool has to be given more time to finish its processes.
How often should you use shock in a pool?
A swimming pool should be shocked once every 3 to 4 weeks if the pool condition is clean, clear, and in normal chemical proportions. This is usually unachievable by many pool owners.
Distortions are undergoing in their swimming pools, and shocking will be needed more frequently than once in 3 to 4 months.
Suppose a bloom of algae appears uncontrollably, a pool shock. After several pool parties or excessive swimming activities, especially in commercial swimming pools, test the chlorine level to confirm if it is required and shock afterward. Shock should be carried out in human-influenced contaminants like urine, feces, or vomit.
Chlorine levels can drop due to unfavorable weather conditions, fault filtration systems, or operational error occurrences; pool shock can easily stabilize the chlorine content in the swimming pool.
Notice that despite getting a normal pH level, cyanuric level, and other chemical constituents, you are getting a low chlorine level. It might be a directive that chloramines are forming with present nitrates. Shock can occur if this is noticed too.
While there are disadvantages of over shocking swimming pools, there are lesser chances of not having signs you are over shocking. The pool shock manufacturer’s manual contains the application and the intervals that should be put after each application.
For a commercial or frequently used pool, shocking should occur once in 1 – 2 weeks.
Final Thoughts
Pool shocks are also used to raise chlorine levels, clean stains, and spot-treat colonies of algae. Put in mind never to mix any other thing with pool shock except water.
They are usually very toxic in reaction and will be harmful to you. Wear protective gear in operation.
Make use of your test kit often to be aware of your water condition and never assume anything with the swimming pool’s water surface.