Lime-Scale stains are a particular problem on many swimming pools, Calcium often called “lime scale”, occur around the top edge of a pool and look like white or gray crusty deposits. The build up of scale occurs over time and is more often than not caused either by hard water or by minerals that seep out of nearby tile mortar. If left in place, they may result in permanent stains on the tile as well as causing the pool to look dirty and unattractive.
Removing the calcium deposits from pool tiles will require some physical effort. Unfortunately, you’ll have to repeat the process periodically, since the stains often return. Once you have removed the stains and have balanced the total Alkalinity of the swimming pool it should just be a case of a little elbow grease occasionally to the boarder tiles to keep your pool looking pristine.
A point to note, border tiles which are white or of a light color will always tend to look dirtier and grubbier in areas (Benitachell, Moraira, Cumbre del Sol ) where the water is hard.