You don’t need to drain the whole pool to patch a pool liner, but be prepared to dive in with your swimsuit and goggles to patch a leak below the water level. By draining the pool, you can actually expose the liner to more harsh conditions, like wind and sunlight, that cause the tears to worsen. It’s best to use the ink test and waterproof patches or tape to identify the leak and patch it up.

Vinyl pools are the least expensive for installation thanks to the relatively low cost of vinyl pool liners. However, vinyl liners do not last as long as fiberglass or concrete designs, which could balance out the cost of the pool overall depending on its size.

A fiberglass pool lasts up to 30 to 50 years with proper maintenance. For the longest possible lifespan, keep your pool water pH as close to seven as possible. Test your water levels regularly, run your pool filter daily, and avoid draining the pool. Once your pool is 20 to 30 years old, you can prolong the lifespan by refinishing the shell.

Chlorine performs several functions, depending on where and how you use it. In drinking water, chlorine in small amounts kills potentially harmful bacteria. It's also a common ingredient in detergents for its whitening properties. Most people associate the chemical with pool use, where it works to kill and control bacteria, germs, and viruses in the water.