Calcium hypochlorite is the most commonly used pool shock with a typical chlorine level of between 50 to 80 percent.
12.5% Liquid Chlorine Pool Shock – Normal Dosage: 1 gallon of shock per 10,000 gallons of water. Shock Dosage: 2 gallons of shock per 10,000 gallons of water.
This will give you an idea of how much shock you need. The general recommendation is to use 1 pound of cal hypo shock for every 10,000 gallons of pool water, and 10 ounces of sodium hypo with around 12.5% chlorine to sanitize your 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.
When you're shocking a pool, the goal is to raise the free chlorine level of the pool water to roughly 10 times the combined chlorine level.
Typically for granular shock, you'll need one pound for every 10,000 to 13,500 gallons of pool water.
How Often Should I Shock My Pool? Shocking your pool regularly will help to keep the water clean and free of contaminants. You should aim to shock your pool about once a week, with the additional shock after heavy use. Some tell-tale signs that your pool needs to be shocked are cloudy, foamy, green, or odourous water.
Similarities Between Liquid Chlorine & Powdered Shock
Similarly, both forms have a higher concentration of available chlorine than those used in daily chlorination. They also both kill nearly all living microorganisms, bacteria and contaminants with ease.
It Should Not Be Done Together
This is because when you mix chlorine and algaecide together, it renders both of them useless. Hence, you should first shock the pool and wait for the chlorine levels to fall below 5 PPM.
Liquid chlorine and granular shock have the same active chemical that sanitizes your pool, what changes is the strength and the way you use it. Liquid chlorine is less costly, unstabilized and comes in liquid form. Granular shock is stabilized and comes in a solid form that dissolves in your pool.
Light Green or Teal Pool Water:
To double shock, you will need to add 2 pounds for every 10,000 gallons of water. For instance, if you pool is 20,000 gallons, you will add 4 pounds of shock.
For every person who uses the pool each day, you will require a further 10 grams of chlorine. Example – A 50,000 litre pool will require up to 200 grams of chlorine and if 5 people use the pool a further 50 grams of chlorine is required = total of 250 grams per day.
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.
How much shock do I need to shock my pool? A simple ratio and a standard rule of thumb to follow when you shock your pool is to dissolve one pound of either calcium hypochlorite or sodium dichlor for every 10,000 gallons of pool water.
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.
There are three primary types of chemicals that are used for pool shock purposes, which include calcium hypochlorite, sodium di-chlor, and potassium monopersulfate. Calcium hypochlorite is likely the most effective pool shock available because of how strong the chemical is compared to the two other options.
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!
Can you put too much shock in a pool? SKIMMER NOTES: It's unlikely but it could happen. It would take a lot of shock to really make the water unsafe for swimming. The best way to make sure you're safe to swim is to test your pool water and make sure free chlorine levels are between 1-4ppm for healthy swimming.
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.
You should wait one hour per pound of shock product added, and then test the water to confirm the pH and chlorine are in the proper range before letting anyone enter the pool. As a reminder, you want your pH to be between 7.2 and 7.8ppm and your free available chlorine to be 1-4ppm for safe swimming.
Adding chlorine besides the shock can increase the chlorine content in the water which can make the entire shocking process useless. Hence, it is better if you don't use the shock and chlorine at the same time. The best time to add chlorine to the pool water is after you have shocked the pool.
Shocking your pool isn't necessary, although, it's not a bad idea either. If you get an extremely heavy rain fall, you could shock your pool for good measure. This will help fight off any contaminants that the rain may have brought to your pool.
It's often recommended to shock your pool once a week. If you don't do it every week, you should at least do it every other week. This is necessary to maintain your pool's water chemistry. If you have a lot of people over in your pool or have a party, you may want to shock your pool more frequently.
Although it's generally recommended that all the pool water undergo filtration every 24 hours, the pump does not need to run all the time. A proactive, productive and energy-saving maintenance activity is to remove the debris floating on the pool surface with a hand-held skimmer.
Brown pool water is often caused by metals (iron) becoming oxidized in the pool water. If you shocked your pool water and it turned brown you probably have metals. Oxidized iron usually turns a brown or rusty color in the water.