does anyone know what this white residue on the bottom of my pebble tec is. it appeared all of a sudden and its extremely hard to brush off. it just leaves a little cloud of white behind the steel brush im using on it. brushed it for hours and it doesnt seem like im getting anywhere. i thought maybe calcium.
i keep the chlor,ph and alk @ 5.0/7.6/90. i just recently dropped the ph to 7.4 to see if it would make brushing easier. still the same though.
two weeks before the white showed up i noticed a light cloud of algae coming up when i brushed. phosphates were 2500 so i treated it and brought them down to 100 since.
i just had a guest house constructed in my back yard and landscaped aswell. it appeared just around the time construction finished. wasnt sure if that could have contributed to it somehow since ive never had this problem before.
im trying to think of anything else that happened in or around the pool that wasnt the usual everyday occurrence but i think thats it.
anyways if anyone has an idea of what this could be please let me know, id really appreciate it!