You can’t expect to fill a swimming pool with water and neglect routine maintenance. Soon, the water in your swimming pool will become stagnant and unhygienic. The water will start to change color and underwater surfaces become slippery, due to bacterial and algae growth. You need chemicals to sanitize your pool and balance its pH and mineral levels. Chlorine: Chlorine is the most affordable and popular chemical product to sanitize your pool’s water. It’s a strong oxidizer that destroys molecules of contaminants or organic matter from the inside out. Free chlorines reach organic molecules and form chloramines, which produce a distinctive scent. Shock: The purpose of shocking your pool’s water is to unbind or oxidize chloramines (inactive chlorine by-products). Shock is simply highly concentrated chlorine that you should use after heavy rain or using your pool constantly. Shock neutralizes the by-products of sanitizers and kills off microorganisms. It is sold separately to regular chlorine. Bromine: Bromine is an alternative element that works like chlorine and it works better for warm water with higher pH. However, Bromine is less stable when exposed to UV light. When you add bromine to pool water, it won’t produce a harsh odor and won’t cause eye irritation. Cyanuric acid: Cyanuric acid is a stabilizer that protects free chlorine from UV exposure. Unless your indoor pool is exposed to sunlight at certain times of the day, you don’t need to add cyanuric acid. Maintain about 70ppm of cyanuric acid in chlorinated pool water, if UV exposure is constant during the day. Algaecide: In some cases, chlorine and shock are not enough to inhibit algae growth, especially in a humid, warm climate. Certain algae species grow very quickly and are hard to get rid of. Uncontrolled algae growth will make the water looks cloudy and it may potentially harm your health. Flocculent: Flocculent clumps microorganisms together, so they will sink to the pool’s floor, which can be removed more easily later. Improper use of flocculent may leave fine dust, so you may leave this task to a professional pool cleaner.