Automatic Pool Sanitizers - The Basics
Chlorine and bromine generators
These electrical units generate chlorine or bromine from special salts added to the water; some units regenerate a bromine bank already in the water. Chlorine and bromine generators are great for maintaining a sanitizer residual, although periodic shocking is still required.As water passes through a chlorine or bromine generator, a sensor measures the sanitizer level. If it is law, the unit starts producing more sanitizer from special salts in the water. Once the sanitizer level is in the proper range, the sensor tells the unit to stop producing chlorine or bromine.
An ozonator produces and releases ozone — an effective sanitizer — into pool or spa water. However, ozone doesn’t last long in a water environment. Once it kills bacteria, the ozone reverts to oxygen and either dissolves into the water or escapes into the air. There’s no way to maintain a measurable ozone residual to ensure the water is sanitized as new contaminants are introduced. Therefore, an ozonator must be used in conjunction with small amounts of chlorine or bromine. There are two types of ozonators: UV and corona discharge. A UV unit creates ozone with a special lightbulb, which needs to be replaced after many months. A corona discharge unit has a special cell that produces ozone. Corona discharge ozonators cost more than UV ozonators, but they don’t have any bulbs that need replacing.
As water flows through these electrical devices, they introduce silver, copper, and zinc ions into the water. These ions are powerful sanitizers. Like ozone, however, there’s no way to maintain a measurable ion residual in the water, so ionizers must be used in conjunction with a halogen-based sanitizer to guarantee a sanitizer residual.
These devices use a combination of silver, copper, and zinc to sanitize water. Some mineral purifiers are simply perforated cylinders that fit inside cartridge filters, whereas others are plumbed in-line along with the other pool equipment. As water flows through a purifier and over the mineral bed, it picks up ions that kill bacteria. Mineral purifiers last several months, but they do not create a sanitizing residual, so they must be used with chlorine or bromine.