If you own a swimming pool, shocking or super chlorinating the pool falls under a regular maintenance routine. To understand when is the right time to shock your pool, you must first know the reasons why pool shocking is required.
The main reasons for shocking a pool are –
- To kill algae and make the pool clean
- To make the pool bacteria-free (bacteria can come from various sources like bather waste)
- To reduce chloramine and contaminant levels
- To get water clarity or to clear cloudy water
- While opening and closing down the pool for the season
- To get the pool water chemistry right
There are various ways of shocking a pool. However, chlorine is the most widely used and the most effective ingredient that’s popularly used for the purpose. Chlorine has been used for centuries to purify drinking water and is perfectly safe to use in pools when used in the right concentration. It is extremely effective when it comes to killing germs, bacteria, and viruses. However, when it comes to shocking the pool with chlorine, you have two choices – granular chlorine and liquid chlorine.
Granular chlorine vs Liquid chlorine
When shopping for pool cleaning supplies, you may wonder which one to put in your basket, granular chlorine or liquid chlorine? Taking a deeper look into the difference between the two will help you choose the right one.
Granular chlorine
The most popular form of granular chlorine or powder chlorine is calcium hypochlorite. Other versions available are dichlor or sodium dichloro-s-triazinetrione and lithium hypochlorite. Calcium hypochlorite is an ingredient used in bleaching powder and for disinfecting pools. Solid forms of chlorine are stabilised and can be distributed in many ways when shocking a pool. It can be dissolved in a bucket of water and added to the pool or introduced through automatic chlorinators (available in the form of tablets).
Calcium hypochlorite is the most popular granular chlorine choice due to its high effectiveness in killing algae and the ability to dissolve quickly. It is also one of the cheapest options and is available in various granule sizes. Granular chlorine has lower pH, which means lesser spending on acid for maintaining a proper water pH balance.
Liquid chlorine
Although liquid chlorine is cheaper compared to granular chlorine, it is a form of unstabilised chlorine. It dissolves fast but has effectiveness for a shorter duration compared to granular chlorine. For larger pools, its effectiveness may not be as good as smaller pools. Liquid chlorine is highly corrosive. Using excess chlorine or not using it correctly may damage the pool walls or your fibreglass pool.
What is best for your pool?
What is the ideal pool shock agent for your pool depends on two basic factors.
- The size of your pool
- Your budget
No matter which version you choose for your pool, chlorine should be handled very carefully. For larger pools, chlorine granules are always a better choice.
Steps to follow when shocking a pool with granular chlorine
Following the right steps is important when shocking your swimming pool with chlorine granules.
Step 1
Chlorine is a harsh chemical, so take protective measures. When handling any form of chlorine, it is always better to wear goggles, a respirator, gloves, and clothing that will keep your hands and legs covered. While handling chlorine, be careful not to splash it on yourself and avoid inhaling the fumes.
Step 2
The next step is to dissolve granular chlorine before adding it to the pool water. Take a bucket of water and pour the chlorine granules into it. Carefully read the suggested chlorine-water ratio on the package to add the right amount into your pool. Smaller pools will need less and larger ones more to work effectively. Gently stir with a wooden stick or a PVC pipe to dissolve the granules.
Step 3
Now it’s time to add the liquid form of the shock to the pool. Make sure to keep the pump running while pouring the chlorine into the pool. Pour the dissolved chlorine gently from the bucket into the pool while moving around the edge. It will help better and quicker distribution of the chemical. Don’t splash the chemical.
Step 4
If you notice any undissolved chlorine granules while pouring the liquid into the pool, use a pool brush to move them around and assist in dissolving. If granular chlorine sits undissolved on the floor, it could lead to discolouration of your fibreglass, granite, or vinyl pool. Undissolved chlorine resting on vinyl pool floors can also corrode the soft vinyl.
Step 5
Wait for at least 24 hours before using the pool.
Some important pool shock tips to remember
- Evenings are the best time to shock your pool. The presence of sunlight can interfere with the effectiveness of chlorine. The chlorine may dissolve too quickly without being able to get rid of the pool of contaminants.
- Do not use the pool for at least 24 hours after shocking the pool. The high chlorine level may harm your skin if you enter the pool too soon.
- Chlorine is very reactive. Never mix pool shock with any other substance but water. If mixed with certain substances, pool shock may catch fire, explode, or give out toxic gases.
- Balance the pool water pH to 7.2 – 7.4 before shocking. It will have the most powerful effect on cleaning the water.
- Do not use pool shock with any other water treatment. It may harm more than helping your pool.
- Do not place granular chlorine into a chlorinator or a floater. Chlorine tablets are the right choice for adding to floaters, skimmer baskets, or your automatic chlorinator.
- Always use the entire bag of granular chlorine once you open the pack. Never store opened packets of pool shock that can spill and may get exposed to moisture.
- Store your granular chlorine pool shock away from fire. This chemical is combustible. To maintain its effectiveness for a longer time, store granular chlorine packs in a cool, dry, and well-ventilated area. If exposed to moisture, it may release toxic fumes.
- Use a water testing kit to take a reading of free chlorine before a pool shock. It should always be between 2 – 3 ppm for a healthy pool.
- Check the pH levels of your pool every two to three days. The pH level can affect the effectiveness of chlorine’s capability to sanitise the pool.
- For heavily used pools, pool shock is recommended once a week to maintain proper water chemistry.
- If your pool is extremely dirty, for example, when you first open it for the season, you should double shock it to thoroughly clean the water.
In conclusion, shocking your pool is an essential maintenance practice that helps ensure a safe and clean swimming environment. Granular chlorine is a highly effective and widely used method for pool shocking, thanks to its convenience and affordability. By following the simple steps outlined in this article, you can confidently and safely shock your pool using granular chlorine. Remember to always adhere to the recommended dosage and safety guidelines provided by the manufacturer. With regular shocking using granular chlorine, you can enjoy crystal-clear and healthy pool water all season long. If you want more handy tips and tricks, visit the blog for more information. Now go ahead, give your pool the shock it needs and dive into a refreshing swim!
