Pool Shock Treatment — Make Your Pool Clean & Clear Again

Cloudy Pool

As shocking as it is, algae can easily grow in pools, and one of the best ways of getting rid of it is shocking your pool. The question now is how do you do it and how long does it take to shock a pool. Pool shocking basically means adding chlorine into your pool to kill bacteria and algae. However, unlike ordinary chlorine, the shock treatment oxidizes the chlorine, which turns it into gas and is released in the air. This prevents water cloudiness which ordinary chlorine will cause.

Types of Pool Shock Treatment and How to Use Them

  1. DiChlor Shock

This pool shock is preferable if you live in a warm location. It contains cyanuric acid, which stabilizes chlorine and preventing it from evaporating quickly due to the sun. DiChlor shock also has minimal effects on the pH level of the pool. However, this is not preferable when you use trichlor as your pool sanitizer or when the level of cyanuric acid is more than 110 ppm. It should be added at night and needs not to be pre-dissolved. Also, you should wait 8 hours before swimming in the pool again.

2. Calcium Hypochlorite Shock

The Calcium Hypochlorite shock treatment is an all-around shock treatment plus, it is less costly. It has 65% chlorine and contains calcium, which increases the calcium hardness of the pool water. Due to this, this shock treatment is not preferable for pools with water hardness more than 250 ppm. The treatment should be dissolved first in 5 gallons of water before applying it to the pool for enhanced effectiveness. It should also be applied during the night and wait for 8 hours before swimming in the pool.

3. Lithium Hypochlorite Shock

One advantage of this shock treatment is that it does not need to be pre-dissolved because it quickly dissolves and is calcium free. It is also the most used shock treatment compared to the other types. However, it is more costly and tends to raise the pH of the pool. And, it should still be added during the night and wait for 8 hours before swimming again.

4. Potassium Peroxymonosulfate

This shock treatment is chlorine free and uses bromine instead. It does not need to be pre-dissolved too. Furthermore, you do not have to wait for 8 hours and you can swim in the pool again just 15 minutes after adding it. This shock treatment can also be added even when you put chlorine in the pool.

When Do You Shock the Pool

The best time to shock a pool is during night time. This is because during the day, the sun is out and the temperature is warmer, making the chlorine evaporate faster. In turn, it decreases the amount of chlorine in your pool before it is able to attach and oxidize. Besides, most people swim during the day, and most shock treatment needs 8 hours before your pool is available again for swimming. If you add the treatment during the night, your pool will be ready again in the morning. It is also important to clean your pool first before shocking.

You should at least test your pool weekly if it needs shocking. If your pool water has more free chlorine, it means that your chlorine is killing the bacteria effectively. Also, the frequency of shocking will greatly depend on how often you use your pool and how many people use it. The more often you use it and the more people that swim in it means that you need shock it more frequently. It should also be shocked after heavy rains and storms. Read more about pool shocking here or here.

Pool Shocking Process

Dissolve the shock treatment into a bucket with water. Read the instructions on the shock treatment package that you bought for the concentration. While your filtration system is running, pour the dissolved shock in the front of the return line fitting. This should be done carefully and slowly to avoid any splash which can stain your clothes and irritate your skin. Then, when you have fully poured the dissolved shock, fill the bucket with water again. Do this process until there are no left shock granules at the bottom of your bucket. Wait for 8 hours before using the pool again.

You should do some test to ensure that your pool is safe to swim again.