Both saltwater pools and traditional chlorinated pools use chlorine to disinfect the water, but the primary difference is in how the owner adds chlorine, according to About.com. In the traditional pool, chlorine tablets supply the chemical to the water. In the saltwater pool, a chlorine generator produces chlorine and adds it to the water.
The chlorine generator in a saltwater pool provides a constant supply of chlorine to the water, preventing the spikes in concentration often seen with chlorinated pools. On warm, sunny days, when the sunlight quickly eliminates chlorine from the water, the constant addition helps to prevent the water from turning green, even though the sunlight encourages an algae bloom.
Swimmers often prefer the soft-water feel of saltwater pools. Most of the time, the chlorine level remains low enough to prevent the eye irritation common with chlorinated pools. The active ingredient in both types of pools is hypochlorous acid. No matter how it got into the water, it does not kill algae or germs if the pool pH is not balanced. Even with the saltwater pools, the owner must maintain the pH for proper disinfection.
One of the disadvantages of saltwater pools is that owners should not empty them onto the lawn. While this is a common practice with chlorinated pools, the salt concentration is high enough to burn the grass. Even though the salt is natural, it is not necessarily environmentally friendly.