How to Remove Stains From a Pool
Drain the pool so that all stains can be inspected and cleaned. Never attempt to remove a stain from a pool that has only been partially drained. The chemicals and cleaning agents used in stain removal will contaminate any water remaining in the pool. It is therefore recommended to drain the pool completely so that the entire surface can be inspected.
Make note of the type of pool surface. Your pool will be made of concrete or plaster. Knowing which material your pool exterior is made from will help you choose cleaning solutions formulated specifically for your type of pool.
Inspect the stain to determine its type. Stains in swimming pools are usually one of two types: organic and rust. Organic stains are caused from leaves and other organic material being allowed to settle in the pool to decompose. Iron is the primary source of rust staining. You would also inspect the area of the waterline for evidence of calcium or lime.
Use a cleaning solution that matches your specific situation. If you have a concrete swimming pool and are faced with an organic stain, then buy a cleaning solution developed for removing organic stains from concrete. There are a number of highly specialized products for swimming pool stains, so it is normal to customize the product based on your particular needs. Some cleaners need to be scrubbed with a brush, and others only ask you to pour the cleaner on the stain. Follow the directions that come with your product.
Use a water hose to spray off the area where the stain once was. You will get best results by using a power spray nozzle. Be sure to spray the entire area thoroughly, along with the entire path that the water takes to the drain. It is important to wash away every drop of the cleaning product.
Refill the pool. Add a new supply of your usual water treatment chemicals so that you can restore the water's PH back to normal levels. Once the PH is at normal levels and chlorine is in the water, it is safe to take a dip in the stainfree pool.