A pool shock is essential in maintaining your pool’s chemistry in a balanced state. It is also an effective way of removing algae from the pool to keep the water in a clean pristine condition. If done regularly especially during summer and other high bathing months, a pool shock helps to retain minimum exposure to your family in a domestic pool or patrons in a commercial facility.
So what exactly is pool shock?
In the pool industry, the word “shock” refers to the intentional over-oxidation or over-chlorination of the water chemistry for a given period of time. At normal levels, chlorine is used up by organic materials such as algae, urine, oils, and lotions. When you shock the pool by continually adding chlorine above normal residual levels, you raise the level of chlorine to a higher level than is required by the organic materials. At this level, the annoying algae are eliminated while maintaining a lower concentration of the chlorine at the same time.
The best time to shock a pool is at night. During the day, the sun will dissolve much of the chlorine before it can attach and oxidize. It is also ideal to shock the pool at night because a shock treated pool cannot be used for at least eight hours. Remember to vacuum the pool to remove large debris before giving it a shock treatment.
How often do you shock the pool?
It is advisable to test your pool at least once every week. The test will show you whether you have free or total content of chlorine in the water. If you have more free chlorine content in the water, then the chlorine is killing bacteria more effectively. Total content refers to the amount of chlorine that has already been used up. You’ll need to shock the pool if you have more total than free chlorine amounts. If you don’t have a testing kit, you can tell when the pool needs shocking by a strong smell of chlorine which indicates excessive presence of organics and waste. The strong smell you are getting is actually chloramines.
A shock treatment may also be necessary after a heavy pool usage by guests or after a period of heavy rains and wind. You may also have to shock your pool when you change the water. The shock treatment will bring back your pool’s chemical levels to a healthy range.
How to apply pool shock treatment
Before you shock the pool, it is important to first figure out which shock treatment to use. There are basically four types of pool shock treatment.
Pool shock treatment using calcium hypochlorite
A calcium hypochlorite is ideal for all types of pool shock treatment. It has 65% chlorine and even adds calcium to the pool’s water. This type of treatment is quite simple. All you need to do is to dissolve the calcium hypochlorite in 5 gallons of water then add it directly to the pool. When mixed with water, it will completely dissolve in the pool. This treatment should be done at night because the pool will not be usable for at least eight hours.
Pool shock treatment using lithium hypochlorite
This is the ideal pool shock treatment when you already have calcium in the water. It is calcium free and does not require pre-dissolving. However, you still have to apply the treatment at night because the pool will not be usable for 8 hours.
DiChlor pool shock treatment
This type of pool shock treatment is ideal for those who live in hot regions. What it actually does is to add cyanuric acid to the water, which is a good chlorine stabilizer capable of preventing loss of chlorine via the sun. The treatment does not have to be pre-dissolved but should be added at night and left for 8 hours before the pool can be used.
Non-chlorine potassium peroxymonosulfate pool shock treatment
There are pools which use bromine instead of chlorine. This type of pool shock treatment is used in such pools. Since it is chlorine free, it does not require pre-dissolving before it’s added to the pool. The best advantage of this method is that you can add it anytime and jump into the pool 15 minutes later.
While applying any type of pool shock treatment, observe the right safety measures such as wearing gloves and protective eyewear. Use warm water to dissolve the shock in a bucket of water and stir well using a wooden stick. Whether pre-dissolved or not, the shock should be added to the pool in a slow gradual process.