My pool cleaner inadvertently left the discharge valve open causing a 30% loss of water before being noticed.The pool was filled from our well supply and the once sparkling blue water in the pool was now a very light teal colour.I shocked the pool with powdered chlorine and the undissolved powder has badly stained the ceramic tiles on the base of the pool.No amount of scrubbing with the pool brush will remove the black stains.What are my options?I really don't want to drain a 60,000 litre pool.
THX Steve
THX Steve