Pool Chemicals

Keeping Your Pool Water Sparkling Clear

Tips for the right chemical balance

Testing your pool 2-3 times a week is important to maintain adequate water balance and sanitizer levels plus to insure swimmer comfort. Although drop-type tests are best, test strips are a quick (30 second) means to test the pool for adequate sanitizer levels as well as pH and total alkalinity. Proper testing also ensures that calcium levels are maintained and that there are no metals present in the pool water. You can buy test kits at your local pool store, or take a sample of the pool water to them for testing. Many pool stores will do this for free. Below is an example table of the recommended levels to look for when testing.

Most often you’ll find the pH level is high; the best way to lower pH is by slowly pouring “Muriatic Acid” (AKA Hydrochloric acid) directly into the pool while the pool pump is on and the water is circulating. However, granular acid (pH Minus or Decreaser) is safer to use alternative than Muriatic Acid. If pH is high, add a small amount of Muriatic Acid and retest the water after about 6 hours of continuous filtration, readjusting pH as needed. This will prevent “bouncing”. If you have a true pH bounce problem, that is typically due to a LOW Total Alkalinity issue; once properly adjusted, the pH should maintain itself well over a period of 1 to 3 weeks depending on rain, use, etc.

What's the Right pH Level of Pool Water?

Best Practices

If swimmers are having a problem with “burning eyes,” high or low pH is probably to blame, not high chlorine.

Follow up the next morning with a maintenance dose of algaecide. Algaecides are surfactants that work on pool surfaces to prevent algae from growing.

Shock the pool weekly. As it works to clean your pool, chlorine binds to other chemicals like ammonia and nitrogen, which not only render it effectively inactive, but also create an irritant that can cause skin conditions.

Chlorine vs Bromine

The difference between chlorine and bromine is that once chlorine combines with bacteria or harmful organics to kill them, most of the chlorine is used up and will no longer work to sanitize your swimming pool. This “combined chlorine” will be burned off by the next shock treatment and removed from the pool water by the filter. When bromine combines with bacteria in pool water, the bromine is still active but combined with the bacteria and organic matter to neutralize these harmful contaminants. When you shock a bromine pool, the shock treatment only burns off the harmful contaminants, leaving a good portion of the bromine behind in the pool water. The bromine left behind is available to sanitize the pool again. The result is that the volume of bromine tablets needed to sanitize a swimming pool is noticeably less than the volume of chlorine needed to do the same job.

There are definite advantages and disadvantages to using bromine. Bromine is considered better by some pool owners because bromine is usually much less irritating to the skin and eyes. Many pool owners with naturally sensitive skin prefer bromine; however bromine is in the same periodic group as chlorine, so it may not help people who are allergic to chlorine. The disadvantage to bromine is that the chemical costs a good deal more per pound than chlorine. Because it’s so stable, moreover, it can also be harder to wash its smell from your skin or swim wear. Overall, bromine isn’t a great alternative to chlorine for a full size pool, so consider using it for smaller facilities such as hot tubs or Jacuzzis. Bromine is available in tablet form and can be added to pool water using a chemical feeder to dissolve the tablets. Special note: bromine CANNOT be stabilized with cyanuric acid.

Questions & Answers on on Pool Chemicals

What chemicals are used in swimming pools?

While we don’t recommend the use of many pool chemicals (we recommend a mineral pool), there is a pool chemical inventory that all chlorine and salt water pool owners should alway have on-hand. You should always have 1) chlorine tables, 2) pool shock, 3) pool pH up, 4) pool pH down, and 5) a test kit with strips. However once a year you should always balance your pool, and that may require, a) sanitizers like TriChor, DiChlor or Bromine, b) oxidizers such as calcium hypochlorite and chlorine free shock, c) water balancers like alkalinity increaser, calcium hardness increaser and chlorine neutralizer, and d) special chemicals such as algaecides, clarifiers and enzymes.

Have a Question about Pool Water? Call Crestwood at 607-786-0010

How do you balance pool chemicals?

The pH level in your pool should be about the same as the pH level of human tears, 7.2, though in the range of 7.2 – 7.6 is optimal. Chlorine is about 10 times more effective at sanitizing your water when the pH is at 7.2 rather than at a high ph level of say 8.2. pH can best be measured with a drop-type test kit versus a test strip, which can be easily misread. Most often you’ll find the pH level is high; the best way to lower pH is by slowly pouring “Muriatic Acid” (AKA Hydrochloric acid) directly into the pool while the pool pump is on and the water is circulating. However, granular acid (pH Minus or Decreaser) is safer to use alternative than Muriatic Acid. If pH is high, add a small amount of Muriatic Acid and retest the water after about 6 hours of continuous filtration, readjusting pH as needed. This will prevent “bouncing”. If you have a true pH bounce problem, that is typically due to a LOW Total Alkalinity issue; once properly adjusted, the pH should maintain itself well over a period of 1 to 3 weeks depending on rain, use, etc.

Do pool chemicals expire?

If you’re a chlorine or salt water pool owner, buying pool chemicals in bulk is a smart path to take. However, not all pool chemicals have a long shelf life. Most liquid acids and dry pool chemicals have a long shelf life if they’re kept away from excessive heat and moisture. Products that have the most common short shelf life are a) liquid shock, b) test strips, and c) reagents. All other chemicals may vary based on the supplier’s packaging, and again where and how you store the chemicals. If you live down south where it is excessively hot or warm, you’ll want to store your pool chemicals in rooms that maintain a 35° to 75º temperature.