HELP! Vinyl discolouration in a pattern

[Jane818]

Hi everybody,

I've recently had no choice but to enter the forum to ask for your advice. After one year of installing a new inground pool, my pool started to discolour in a linear pattern-- strips of dark and lighter colour. My pool company blamed us for causing chemical imbalances in the pool and he also blamed the robot. IF this were in fact true, the pattern wouldn't be linear and the robot doesn't run in straight lines then decides to skip a few inches to the left or right. Secondly, I contacted the vinyl company and they tell me it's something underneath the liner that the pool company put. I don't think this is the case because the pattern staggers at the seams. I watched a time lapse video on my phone and there's no foam or duct tape underneath the liner, despite the company's claim. Now, I'm at a standstill because this is the third year into my pool and it looks horrendous. Even worse, nobody wants to take responsibility. The pool company that I thought would vouch for me (mind you they're pretty big in Toronto) has decided to find some other reason that points to us. Please help!
I'd attach a photo but I don't know how to. And I can't find anything on the internet like this.