Borates provide a range of benefits to the swimming pool.  Since borates
soften the water, they provide comfort to the swimmer by reducing skin
irritation.  They also provide excellent buffering properties that decreases
chlorine usage.  As a corrosion inhibitor, they reduce corrosion to metal
pipes and fittings.  Since borates are inorganic compounds that do not
convert to gaseous forms, it rarely needs to be replaced in the pool during
the season unless the pool has a leak and new water is routinely being added