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Chlorine

Chlorine is the most common form of sanitizer used in pools today. Chlorine’s job is to keep your water crystal clear and provide you with a safe environment to swim. It achieves this by killing bacteria and algae and oxidizing (burning up) any particles to small for your filter to remove.

How Chlorine Works
Chlorine that purchased is typically combined with other compounds to be safe to handle. Once the chlorine comes in contact with water, it changes to an active form that kills bacteria and algae in your pool. This killing form is called hypochlorous acid. As the chlorine destroys the bad guys, the chlorine level in your pool will be reduced or get used. Sunlight and splashing will deplete your chlorine level. This is the main reason it is important to keep proper levels of chlorine in your pool at all times. With all of these factors diminishing your chlorine level, there is not much available chlorine to fight off any other bad guys that your water may come in contact with.

Types of Chlorine

There are two main types of chlorine that are used to keep pools from becoming a swamp: stabilized and unstabilized chlorine. Stabilized chlorine contains cyanuric acid, which protects the chlorine in your water from ultraviolet rays from the sun. Unstabilized chlorine does not have cyanuric acid in it, so it must be added separately to your pool water. When using unstabilized chlorine, you will add chlorine more frequently.

Stabilized Chlorine
There are two types of stabilized chlorine:

Dichlor
DICHLORO-S-TRIAZINETRIONE, or called sodium dichlor, has 65% available chlorine. Dichlor is a white granular form of chlorine that has a slightly low pH, but for the most part can be considered neutral. Since dichlor comes in granular form, you cannot use it in chlorine feeders or automatic chlorinators. Dichlor dissolves fast when added to water American Sale recommends to pre-dissolve it in a bucket of water before use.

Trichlor

     TRICHLOR-S-TRIAZINETRIONE, or more commonly known as trichlor, has 89% available chlorine. Trichlor dissolves slowly into pool water, therefore is found mostly in tablet or stick form. These tablets and/or sticks are placed in a chlorine feeder or automatic chlorinator to help maintain proper levels of chlorine. Using an automatic chlorinator or feeder eliminates the hassle of constantly adding chlorine to your pool water. Most chlorinators and feeders can hold a one to four week supply of chlorine, and can be adjusted if the demand for more chlorine is needed. You will find that when there is more sun or when you have more swimmers than usual, you will need to increase the amount of chlorine feeding into your pool.

Unstabilized chlorine
     Unstabilized chlorine does not have an UV protector. Unstabilized chlorine is available in liquid or granular form. The different types of unstabilized chlorine are: sodium or calcium hypochlorite.

Sodium Hypochlorite:
     Sodium Hypochlorite is also known as liquid chlorine. Chlorine in this form is easy to use and quickly increases the chlorine level. Liquid chlorine has a pH about 13 ... with 12% to 13% active chlorine. Since liquid chlorine is not stabilized, sunlight will cause the chlorine to dissipate quickly. You will need to add more chlorine because of this and need to add it more frequently. Liquid chlorine does NOT have a long shelf life. The longer it is stored, the weaker the chlorine gets, so make sure when purchasing liquid chlorine to use the product within a short period of time.
     Liquid Chlorine will add a tremendous amount of total dissolved solids (TDS) to your water, making all your other chemicals less effective.

Calcium Hypochlorite
     Calcium hypochlorite is a white powder with a high pH of 11.8 and 65% active chlorine. Like liquid chlorine, it will dissipate quickly with sunlight. However, calcium hypochlorite is stable and can be stored for long periods of time, unlike liquid chlorine. This product should be stored in a dry, cool place and can ignite if contaminated.

Comparing Stabilized and Unstabilized
     On average, 3 ounces of trichlor will give about the same sanitizing power that one-gallon of liquid chlorine or a 1 lb. bag of calcium hypochlorite. We definitely recommend stabilized trichlor because of this. A majority of our customers use trichlor because of these benefits:

Easier to store
You’ll use less chlorine
Only needs attention once a week
Costs less per season

Stabilized chlorine is definitely the better bang for your buck!

Green Grass is Good—Green Pool Water is NOT!

     Now that your pool is properly balanced, you must not forget to sanitize it. The biggest problem with pools is algae, the biggest reason why, is not enough chlorine. To maintain crystal clear, bacteria free water, you can use any of the different types of chlorine discussed. You should keep the chlorine level in a range of 1 to 3 ppm. Your water will remain sanitary as long as the chlorine level does not drop below 1 ppm.
     Every day your chlorine usage is different. This is dependent on many factors such as how many swimmers, weather, as well as dirt and debris in your pool water. The more factors present, the more your chlorine is being used. Since the amount of chlorine in your water is changing everyday, it is recommended that you test your water chlorine level daily.

What’s that smell?
     If your pool water smells like there’s too much chlorine, actually it’s telling you there’s not enough. When you add active chlorine to your pool, it automatically begins to do its job by attacking any algae and bacteria present in the water. The chlorine that was used is now called combined chlorine. The chlorine remaining that can still be used to fight is called free chlorine. Only free chlorine is left as the active chlorine to keep your water sanitized.
     Combined chlorine, or chloramines is chlorine being tied up by ammonia groups. These chloramines are what cause skin and eye irritation and also that strong chlorine odor that everyone has experienced. When chlorine is tied-up in chloramines, it is not an effective sanitizer.
     There are test strips that test for free chlorine and total chlorine. Ideally, total chlorine should equal free chlorine, which tells you none of your chlorine is being tied-up. If you show a high amount of total chlorine, but hardly any reading on free chlorine, your test kit is telling you that your chlorine is being tied up in chloramines. In order to activate this chlorine you must superchlorinate ... or shock your pool water.
     Shocking your water means bringing your chlorine level up to 10 ppm. Once you raise your chlorine level to this range, the chloramines will break down and free your chlorine that has been tied up. You should shock your pool on a bi-weekly basis or as often as needed.

Just because you shocked your pool does not mean you can refrain from chlorinating the rest of the week. As you might have read, some of your chlorine is used up right away, some is held on reserve. After the shocking, as part of normal maintenance, you should always add a routine amount of chlorine to your water once your chlorine level returns to 3 ppm.
What if you need to shock your pool and you have a party in 2 hours? There is another chemical you can purchase made by Proteam called Shock and Swim. Shock and Swim is a chlorine free shock, which allows you to swim in 15 minutes!

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