My 20000 gallon gunite pool is about 3 weeks old now. Part of the initial fill was with well water (high in iron - therefore I'm assuming stains are iron related). I ran the garden hose all night before water tanker arrived in morning and filled with 18K gallons. I brush pool twice a day.
Now I am noticing some light brown or tan colored stains near the main drain and swimout. They do not brush out. What should I do next? The water is balanced - I have Ben's test kit.
My readings are:
FC = 2
ALK = 90
CAL= 160
CYA = 40
PH = 7.5
TEMP = 78