Water Test Results
FC: 5 ppm
CC: 0 ppm
Alk: 90 ppm
CH: 120 ppm
CYA: 45 ppm
Currently shocking at 20 - 24 ppm (I used 2 gallons of 12.5% chlorine and 3 bags of 73% Cal-Hypo)
Here is a picture of the bottom drain at the deep end (8.5 feet). I have circled an area of the stain portions of the liner. and also indicated two areas where there is no stain.
The stains are in portions of the shallow end as well (3.5 ft) and in the corners of the transition to the deep end ramp.
The stains don't scrub off with a brush, even with some force, but they seem to fade after shocking?
Does this look like a mustard algae bloom.: