Certified Pool Operator Practice Test 2025 – All-in-One Guide for Exam Success!

Calcium chloride is commonly used in pool maintenance to increase the calcium hardness in the pool water. Calcium hardness refers to the amount of dissolved calcium in the water and is important for keeping the pool's pH levels stable and preventing damage to the pool surfaces. The other options are incorrect because

B: Lowering the pH level is usually done using acidic chemicals such as muriatic acid or sodium bisulfate.

C: Total alkalinity refers to the levels of alkaline substances in the water and can also be adjusted using specific chemicals.

D: Sanitizing the water is a separate aspect of pool maintenance and is usually done using products containing chlorine, bromine, or other chemicals that kill bacteria and other harmful organisms.