Shock is liquid or granular chlorine. You should add one gallon (or one pound) of shock per 10,000 gallons of pool water every week to two weeks. During hot weather or frequent use, you may need to shock more frequently.
Chlorine has a low pH level, and in order to maintain your pool water's clarity and balance, shocking weekly will allow you to quickly raise the chlorine level, which will rid the pool of contaminants, without lowering the water's pH levels.
Most floating chlorinators can hold anywhere from two to eight weeks worth of chlorine, depending on conditions such as the season and your pool's size. An automatic feeder works in a similar way, allowing it to mix with the pool water slowly and deliberately. This type generally comes in a large bucket.
During the bathing season, the chlorine is "burned off" by the sun and when you are using the pool a lot, you also need to add up chlorine. As a rule, you must add chlorine every day to keep the right balance during the bathing season.
The Bottom Line about Pools and Chlorine
As mentioned above, you could probably swim in a pool without chlorine without any major health issues. However, long-term use of a pool lacking chlorinated H2O could make you sick or, at the very least, contribute to rashes and other types of skin irritation.
You might have an infestation of algae, fungus or bacteria that can deplete normal chlorine levels and it is possible for this to occur without many visible signs. Your pool may appear to have a dusty look on the pool bottom. If you brush it and it clouds the water, then it is most likely a Mustard Algae.
Chlorine is used to kill germs and bacteria in pool water, so it plays an important role in keeping the water clear. The pool's pH level, which measures how acidic or alkaline the water is, influences how effective the chlorine is in keeping the water clean.
Liquid Chlorine has the shortest shelf life of all your pool chemicals, losing up to 50% or half of its potency six months from when it was first opened and up to 90% after a year.
Aim to maintain a chlorine level of 3 to 5mg/l at all times. How frequently you add more chlorine will depend on your usage and bathing habits. It could be daily, every two to three days or weekly. For 1mg/l, add 2g per 1000 litres.
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.
On average, you should check your chlorine levels at least two to three times a week. However, for new pool owners, you may want to begin by checking your chlorine levels once a day. This daily routine gives pool owners time to learn their pool in relation to their swimming habits and weather.
We suggest shocking the pool every week to two weeks; with hot weather or increased use, you may need to shock more often. When tabs run out, replace them.
Properly stored, pool shock has a shelf life of over 5 years.
You can use half tablets too, score them with a screwdriver, and break it in half with your hands, underwater in the skimmer basket.
Sun Down – You'll want to shock your pool in the evening when the sun has gone down. This gives your pool plenty of time during the night to free the chlorine and clean the water. In the morning, you should be able to enjoy your pool. If you shock your pool during the day, the sun's UV rays will dissolve the chlorine.
You can swim with chlorine tablets in the pool if the chlorine tablets are in a container. Getting in touch with those tablets can cause rashes, irritation and eye problems. However, to be in a safe zone it will be better if you wait for 3 to 5 hours till the chlorine levels touch 4 to 6 ppm.
High doses of chlorine, like pool shock, can cause temporary cloudiness as it kills contaminants. High levels of pH, alkalinity, and calcium hardness are more likely to cause cloudy water.
Raise the Level of Pool Chlorine
Raising pool chlorine can be much easier than trying to lower chlorine levels. Simply adding chlorine in the form of chlorine tablets, granular chlorine, liquid shock or powder shock will increase the total amount of chlorine within the pool.
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.
In short, the UV rays produced by the sun have a major effect on chlorine. When exposed to UV rays, chlorine ions begin to separate, which eventually destroys them. And as your chlorine burns away, your sanitizer level drops. This is the very reason why CYA (cyanuric acid), or chlorine stabilizer, exists.
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!