Liner Problem

[chem geek]

By any chance, did you have Trichlor pucks in a floating dispenser in the pool? If the dispenser parked itself in one place, then the acidity and high chlorine level could bleach out and even weaken the liner in that area. [EDIT] Ignore what I just said. You said that this affected area is ABOVE the water line and I can now clearly see that from your pictures. [END-EDIT]

[EDIT2] Well, if I actually READ every post, I might learn something! You actually said you did use a floating dispenser so that would in fact produce very acidic (low pH) and highly chlorinated (high FC) water in the vicinity of the feeder when the pump was off. The only thing is that this would explain bleaching in the area where the water contacts the liner, but I don't see how that would bleach the area above the waterline. If the water level did ever get near the top (from rains?), then that would explain it, but you said the water level never got that high. [END-EDIT2]

Richard