Pre-dissolving is accomplished by filling a clean 5-gal bucket full of pool water. Pour in 1 or 2 lbs. of granular pool shock directly into the water (always add chemicals to water, not water to chemicals). Stir with a yardstick or suitable paddle for several minutes to dissolve the granules.
Needs to be dissolved before you add it to the pool. Must be used after dusk. Allow eight hours to pass after shocking before you can safely swim. Adds about 0.8 ppm of calcium to your water for every ppm of FC added.
Swim-Ready in 15 Minutes
Fast dissolving formula works quickly so you can treat and swim in just 15 minutes.
The Solution
Pre-dissolve the chemical in a bucket of water before you shock your pool. This will allow the shock to disperse more evenly in the water, protecting your liner, pool walls, and floor.
Calcium hypochlorite shock is most commonly found in granular form; however, it can also be found in the form of chlorine tablets. Regardless of whether you use calcium hypochlorite in powder or tablet form, be sure to dissolve the chemical into at least five gallons of water before mixing it into the pool.
Shock is chlorine, in a high dose, meant to shock your pool and raise the chlorine level quickly. Chlorine tabs (placed in a chlorinator, floater, or skimmer basket) maintain a chlorine residual in the water. You do need to use both tabs and shock.
If you need to mildly shock a 30,000-gallon pool by raising the free chlorine concentration to 5 ppm, you need 2.5 gallons of bleach. To raise it to 10 ppm, you need 5 gallons.
To superchlorinate, add AT LEAST 2.5 ounces (5 tablespoons, 75 grams) of chlorine for every 100 gallons (400 litres) of spa water or part thereof. Adding more is fine and never a bad idea.
Answer: After shocking the pool, it will need filtration and circulation. Run the pump as much as possible. Keep the filter clean (daily) until the water runs clear. Be sure to brush the pool often during this process as above-ground pools do not have drains at the bottom.
BUT, if you have to shock your pool during the day in broad daylight, you can still swim after adding shock. It's recommended that you wait one hour after adding shock with the filter running, and then test the water to confirm the pH and chlorine are in the proper range before letting anyone enter the pool.
Shock-chlorination is an essential and effective method of cleaning the pool. But you need to have the pump circulating the water for this to be effective.
A pool filter should be run for a minimum of 6 hours after shocking a swimming pool. This is to allow the filter to clean the water and give the shock enough time to fully mix with the pool water. Running the filter after shocking for 24 hours to 7 days is necessary if the pool has a large amount of algae.
The most common pool stabilizer -- or conditioner -- is cyanuric acid, a slow-dissolving powder or granular product. Pool owners should maintain cyanuric acid levels of 30 to 50 ppm. If the level is too low, there will be insufficient protection against ultraviolet light and chlorine will dissipate.
Pools can immediately turn green after shocking when they have metals like copper in the water. These metals oxidise when exposed to high levels of chlorine which makes the pool water turn green. Adding a metal control product such as Zodiac Metal Remover will help to restore the pool water.
In theory, if you have a cloudy swimming pool, you can add chlorine to “shock it” and clear things up. Chlorine will get the job done. But, the amounts may vary and you may have to really pound the pool with chlorine to get the water totally clear.
Why do you need to shock a pool? Pools are shocked to remove combined chlorine molecules, aka chloramines from the water. Pools are also shocked to remove excess bather waste and bacteria after heavy pool use, contamination events, or for the removal of visible algae in the water.
After Shocking Your Pool
It is safe to swim once your chlorine levels are around 5 ppm or after 24 hours. It is always best to test first!
Before you start pouring shock in the pool, the first step is to brush the sides and floor of your pool to loosen all the algae. Doing this breaks the skin and allows the pool shock to more easily kill the algae. Once you've done this, it is important to make sure you have the proper pH level in your water.
Pool water turns green because of algae in the water. Algae can grow rapidly, particularly when it's warm like Summer, which is why it can surprise you overnight. This generally comes down to an imbalance or lack of chlorine in the water.
Triple shocking requires 3 pounds for every 10,000 gallons of pool water. This is the worst of the worst. I like to refer to this as The Creature From The Black Lagoon. You will need to quadruple shock your pool by added 4 pounds of shock to every 10,000 gallons of water.
Superchlorination, also known as shocking or chlorine shocking, is the process of adding several times more chlorine to the pool than is normally needed so that the chlorine can "burn" through resistant compounds, chemicals, oils and strong types of algae.
This is why many pool experts recommend that you turn down, or shut off, your saltwater chlorine generator (SWG) while you're shocking your pool. Otherwise, you're running the risk of damaging the salt cell. And that could lead to it not generating enough chlorine after the shocking process finishes.
Swimming pool shock contains 12.5% sodium hypochlorite (bleach) vs. 6-8.5% for Clorox (bleach). Some Clorox products go as high as 8.5%. At a 12.5% concentrate, liquid pool shock is approximately 2x's stronger than Clorox bleach.
Household bleach, Clorox and liquid chlorine can all be used to sanitize a pool. They are all types of chlorine. Household bleaches such as Clorox usually contain about 5-6% available chlorine, about half that of pool liquid chlorine. Household bleaches often have unwanted fragrances and colors.
Typically for granular shock, you'll need one pound for every 10,000 to 13,500 gallons of pool water.