Why does a pool need chemicals?

Pool chemicals are used to sanitize and disinfect your pool water and are a necessity for all swimming pools to keep swimmers safe. Chlorine and bromine are common chemicals used for pools and hot tubs, but there are a wide variety of chemicals to use depending on the issue at hand.

What are the benefits of balanced pool chemicals?

The key to safe and clean pool water during your swimming season is to correctly balance your pool chemicals. Keeping your pool chemicals balanced so that your water stays clean and clear will:

What does chlorine do to your pool’s water?

Chlorine is a pool sanitizer, and maintaining the correct chlorine level in your pool during the swimming season is very important. If your chlorine levels are too low, algae and bacteria will begin to grow in the water. If your chlorine levels are too high, it can cause irritation to your skin, eyes, and hair. Maintaining the correct chlorine levels will translate to clear and safe water for your family and friends.

How do you test your pool’s water?

Water temperature, sunlight, pool usage, and the weather can all impact the chemicals in your pool water. It is very important to test your water weekly to ensure your chemical levels are balanced. Test strips are the easiest way to test pool water because they give immediate feedback on the levels of chlorine, pH, alkalinity, and other important balancers needed to maintain crystal clear pool water.

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Shock is the most important chemical used in swimming pools. It is very important to shock your pool weekly, especially after heavy pool use or extended warm weather. Shocking your pool quickly raises the chlorine level in your pool, killing bacteria and algae. Shock typically comes in either liquid or powder form.

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The most common pool sanitizer is chlorine. Chlorine typically comes in either solid (tablet) form, or powdered. The chlorine in your pool works directly with pool shock to disinfect your pool water and kill any bacteria and algae. It is important to keep the correct chlorine level in your pool. High chlorine levels can cause eye and skin irritation, and low chlorine levels can cause bacteria and algae growth, making the pool water unsafe.

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Water balancers

Maintaining the proper levels of PH, alkalinity, hardness, and conditioner/stabilizer are vital in keeping your swimming pool water clean and safe. These levels should be tested and balanced weekly. Keeping your chemicals at the correct levels allows your sanitizers to work to their full potential, translating to a clean, safe pool.

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Algae control

Algae can be one of the most frustrating things to deal with for any pool owner. Even the slightest drop in your chlorine level can cause algae to bloom in your pool within hours. We offer both low concentrate algicides for weekly maintenance applications, as well as high concentrate algae eliminators to quickly kill any existing algae in your pool.

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Water clarifiers

Cloudy water is caused by a variety of issues including weather, dirty filter elements and un-balanced chemicals. Most clarifiers are coagulants, which allow the particles in your pool that are causing the cloudy water to stick together, making it easier for your filter to catch them.

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Opening and closing chemical kits for your pool

Using the right chemicals when you open your pool at the beginning of the season is critical to ensuring your pool water remains healthy throughout the summer. It’s also important to use the right chemicals at the end of the pool season when you close your pool, which will control bacterial and algae growth over winter so that it’s easier to get your pool up and running again come spring.

Our pre- made chemical kits for opening and closing your pool make the beginning and end of your pool season quick and easy. Our opening and closing chemical kits come with everything needed to open or close your pool, along with step-by-step directions.

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Water Testing

Using test strips for your pool, or test kits to testing your water regularly is an important part of keeping your swimming pool’s water safe, clean and healthy. Keeping your chlorine, pH, alkalinity, and other chemicals within the correct range will help you keep your pool water sparkling all season long. Below you will find a guide on water testing and the correct recommended levels for your pool chemicals.

Test Strips

Test strips are the easiest way to test your pool water because they give almost immediate feedback. Simply dip a test strip into a sample of your pool water, wait 10-20 seconds, and compare the test strip to the color grid on the bottle. Typically, test strips can test for chlorine, pH, alkalinity, hardness, and stabilizer (also called conditioner).

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Test Kits

Liquid test kits are simple to use, but most only test for chlorine and pH levels. For accurate results, take a sample from deep in your pool, and use multiple test kits for the most accurate results.

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Water Testing Guide


Chlorine is used in swimming pools to disinfect and kill algae and bacteria. Chlorine comes in liquid, powder, and tablet form. Typically, chlorine is added to your pool water weekly, but additional doses may be needed during very warm weather, or after heavy usage of the pool. The recommended range for chlorine is 1-3 ppm (parts per million). If your chlorine level is too high, irritation of the skin, eyes, and hair can occur. If too low, it is much easier for algae and bacteria to grow.


Biguanide (sometimes referred to as Baquacil) is an alternative to chlorine, and is used as a sanitizer. Unlike chlorine, biguanides cannot oxidize and destroy organic contamination like bacteria or algae. A separate, hydrogen peroxide-based solution is needed on a regular basis to remove any organic contamination. Biguanide will NOT work with any other types of sanitizing systems, as it is based on entirely different water chemistry than chlorine. Biguanide products tend to be a bit pricier than chlorine products, but are less corrosive to pool components and equipment.

To test biguanide levels in your water you can purchase a biguanide test kit and match the colors from the strip to the color on the bottle. An alternative is to use a digital, hand-held tester that can test for biguanide and other levels like pH and alkalinity.


pH is the second most important chemical to balance in your pool. Keeping your pH in the correct range helps all other chemicals in the water last longer and work to their full potential. Ideally, pH should be tested multiple times weekly as rain, weather, and pool usage can fluctuate your pH reading.

The ideal reading for pH in pool water is between 7.2 – 7.8. Low pH can cause chlorine to be less effective, can corrode metals on your pool, and cause irritation to skin and eyes. High pH can cause chlorine to be less effective and can turn the pool water cloudy.

Total alkalinity

Keeping your alkaline levels within the recommended range is very important to your overall water chemistry. Alkaline goes hand in hand with pH, and keeping the total alkaline in the recommended range of 80-120pp will help maintain your PH.

Total Hardness

Total hardness refers to the amount of calcium in your swimming pool water. This should also be tested weekly, as having your calcium level too low or high can cause problems for the structure of your pool. If your calcium level is too low, it can lead to metal corrosion on the wall and rails of your pool. If your calcium level is too high it can cause cloudy water and scaling on the liner, rails, and pool wall. The recommended range for total hardness is 150 – 400 ppm.

Conditioner or Stabilizer

Pool conditioner (sometimes called stabilizer) acts as a sun screen for the chlorine in your pool water. The sun’s UV rays can break down chlorine causing the chlorine level in your pool to drop, especially on hot, sunny days. By keeping your conditioner within the correct range, you can help prevent the sun from burning up the chlorine in your pool before it works to its full potential. The recommended range for conditioner or stabilizer is 30 – 50 ppm.

Pool Chemical FAQs

How often should I shock my pool?

Typically, you will need to shock your pool once a week. Sometimes a second or third weekly dose will be needed if the pool has heavy usage, or if there is a prolonged period of very warm weather. Testing your chlorine level every few days and adding as needed is the best way to maintain proper chlorine levels.

What is the ideal PH level for a swimming pool?

Ideally, 7.4 is the perfect PH level for a swimming pool, as that closely matches the alkalinity of the human body. Keeping the PH level between 7.2 – 7.8 is usually a good guideline to use.

There is algae in my pool. How do I get rid of it?

If you catch the algae bloom fast enough, sometimes shock and chlorine will kill it. If not, a few doses of an algae eliminator, along with an extra shock treatment should do the trick. Keep an eye on your chlorine level, as it probably dropped below the recommended range in order for the algae to grow in the first place.

I have chemicals left over from last season. Are they still good to use?

Water balancing chemicals like PH Up or Down, Alkalinity Control, Calcium Increase, and Conditioner/Stabilizer, have in infinite shelf life as long as they do not get wet, and keep their powdered form. Liquid chemicals like Shock and Algaecides typically have a shelf life of one season. It is best to check expiration dates on these products to be sure.

How long until I can swim after adding chemicals to my pool?

For water balancing chemicals, it is usually safe to swim about 30 minutes after they are added to the pool. Shock and algaecides should always be added to the pool in the evening, when everyone is done swimming for the day. It is safe to swim in the pool 24 hours later. It is very important to have your pump running when adding chemicals to your pool to ensure proper circulation.

Looking for more information? Visit us in store, or contact one of our experienced team members for more information about pool chemicals, test strips and pool testing kits.

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